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Commit | Line | Data |
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16444a8a ACM |
1 | /* |
2 | * Infrastructure for profiling code inserted by 'gcc -pg'. | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally ported from the -rt patch by: | |
8 | * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code in the latency_tracer, that is: | |
11 | * | |
12 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 13 | * Copyright (C) 2004 Nadia Yvette Chambers |
16444a8a ACM |
14 | */ |
15 | ||
3d083395 SR |
16 | #include <linux/stop_machine.h> |
17 | #include <linux/clocksource.h> | |
18 | #include <linux/kallsyms.h> | |
5072c59f | 19 | #include <linux/seq_file.h> |
4a2b8dda | 20 | #include <linux/suspend.h> |
8434dc93 | 21 | #include <linux/tracefs.h> |
3d083395 | 22 | #include <linux/hardirq.h> |
2d8b820b | 23 | #include <linux/kthread.h> |
5072c59f | 24 | #include <linux/uaccess.h> |
5855fead | 25 | #include <linux/bsearch.h> |
56d82e00 | 26 | #include <linux/module.h> |
2d8b820b | 27 | #include <linux/ftrace.h> |
b0fc494f | 28 | #include <linux/sysctl.h> |
5a0e3ad6 | 29 | #include <linux/slab.h> |
5072c59f | 30 | #include <linux/ctype.h> |
68950619 | 31 | #include <linux/sort.h> |
3d083395 | 32 | #include <linux/list.h> |
59df055f | 33 | #include <linux/hash.h> |
3f379b03 | 34 | #include <linux/rcupdate.h> |
3d083395 | 35 | |
ad8d75ff | 36 | #include <trace/events/sched.h> |
8aef2d28 | 37 | |
2af15d6a | 38 | #include <asm/setup.h> |
395a59d0 | 39 | |
0706f1c4 | 40 | #include "trace_output.h" |
bac429f0 | 41 | #include "trace_stat.h" |
16444a8a | 42 | |
6912896e | 43 | #define FTRACE_WARN_ON(cond) \ |
0778d9ad SR |
44 | ({ \ |
45 | int ___r = cond; \ | |
46 | if (WARN_ON(___r)) \ | |
6912896e | 47 | ftrace_kill(); \ |
0778d9ad SR |
48 | ___r; \ |
49 | }) | |
6912896e SR |
50 | |
51 | #define FTRACE_WARN_ON_ONCE(cond) \ | |
0778d9ad SR |
52 | ({ \ |
53 | int ___r = cond; \ | |
54 | if (WARN_ON_ONCE(___r)) \ | |
6912896e | 55 | ftrace_kill(); \ |
0778d9ad SR |
56 | ___r; \ |
57 | }) | |
6912896e | 58 | |
8fc0c701 SR |
59 | /* hash bits for specific function selection */ |
60 | #define FTRACE_HASH_BITS 7 | |
61 | #define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS) | |
33dc9b12 SR |
62 | #define FTRACE_HASH_DEFAULT_BITS 10 |
63 | #define FTRACE_HASH_MAX_BITS 12 | |
8fc0c701 | 64 | |
f04f24fb | 65 | #ifdef CONFIG_DYNAMIC_FTRACE |
33b7f99c SRRH |
66 | #define INIT_OPS_HASH(opsname) \ |
67 | .func_hash = &opsname.local_hash, \ | |
68 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
5f151b24 SRRH |
69 | #define ASSIGN_OPS_HASH(opsname, val) \ |
70 | .func_hash = val, \ | |
71 | .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), | |
f04f24fb | 72 | #else |
33b7f99c | 73 | #define INIT_OPS_HASH(opsname) |
5f151b24 | 74 | #define ASSIGN_OPS_HASH(opsname, val) |
f04f24fb MH |
75 | #endif |
76 | ||
2f5f6ad9 SR |
77 | static struct ftrace_ops ftrace_list_end __read_mostly = { |
78 | .func = ftrace_stub, | |
395b97a3 | 79 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB, |
33b7f99c | 80 | INIT_OPS_HASH(ftrace_list_end) |
2f5f6ad9 SR |
81 | }; |
82 | ||
4eebcc81 SR |
83 | /* ftrace_enabled is a method to turn ftrace on or off */ |
84 | int ftrace_enabled __read_mostly; | |
d61f82d0 | 85 | static int last_ftrace_enabled; |
b0fc494f | 86 | |
2f5f6ad9 SR |
87 | /* Current function tracing op */ |
88 | struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; | |
405e1d83 SRRH |
89 | /* What to set function_trace_op to */ |
90 | static struct ftrace_ops *set_function_trace_op; | |
60a7ecf4 | 91 | |
345ddcc8 | 92 | static bool ftrace_pids_enabled(struct ftrace_ops *ops) |
e3eea140 | 93 | { |
345ddcc8 SRRH |
94 | struct trace_array *tr; |
95 | ||
96 | if (!(ops->flags & FTRACE_OPS_FL_PID) || !ops->private) | |
97 | return false; | |
98 | ||
99 | tr = ops->private; | |
100 | ||
101 | return tr->function_pids != NULL; | |
e3eea140 SRRH |
102 | } |
103 | ||
104 | static void ftrace_update_trampoline(struct ftrace_ops *ops); | |
105 | ||
4eebcc81 SR |
106 | /* |
107 | * ftrace_disabled is set when an anomaly is discovered. | |
108 | * ftrace_disabled is much stronger than ftrace_enabled. | |
109 | */ | |
110 | static int ftrace_disabled __read_mostly; | |
111 | ||
52baf119 | 112 | static DEFINE_MUTEX(ftrace_lock); |
b0fc494f | 113 | |
b848914c | 114 | static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; |
16444a8a | 115 | ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; |
2b499381 | 116 | static struct ftrace_ops global_ops; |
16444a8a | 117 | |
2f5f6ad9 SR |
118 | #if ARCH_SUPPORTS_FTRACE_OPS |
119 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 120 | struct ftrace_ops *op, struct pt_regs *regs); |
2f5f6ad9 SR |
121 | #else |
122 | /* See comment below, where ftrace_ops_list_func is defined */ | |
123 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip); | |
124 | #define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops) | |
125 | #endif | |
b848914c | 126 | |
0a016409 SR |
127 | /* |
128 | * Traverse the ftrace_global_list, invoking all entries. The reason that we | |
1bb539ca | 129 | * can use rcu_dereference_raw_notrace() is that elements removed from this list |
0a016409 | 130 | * are simply leaked, so there is no need to interact with a grace-period |
1bb539ca | 131 | * mechanism. The rcu_dereference_raw_notrace() calls are needed to handle |
0a016409 SR |
132 | * concurrent insertions into the ftrace_global_list. |
133 | * | |
134 | * Silly Alpha and silly pointer-speculation compiler optimizations! | |
135 | */ | |
136 | #define do_for_each_ftrace_op(op, list) \ | |
1bb539ca | 137 | op = rcu_dereference_raw_notrace(list); \ |
0a016409 SR |
138 | do |
139 | ||
140 | /* | |
141 | * Optimized for just a single item in the list (as that is the normal case). | |
142 | */ | |
143 | #define while_for_each_ftrace_op(op) \ | |
1bb539ca | 144 | while (likely(op = rcu_dereference_raw_notrace((op)->next)) && \ |
0a016409 SR |
145 | unlikely((op) != &ftrace_list_end)) |
146 | ||
f04f24fb MH |
147 | static inline void ftrace_ops_init(struct ftrace_ops *ops) |
148 | { | |
149 | #ifdef CONFIG_DYNAMIC_FTRACE | |
150 | if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) { | |
33b7f99c SRRH |
151 | mutex_init(&ops->local_hash.regex_lock); |
152 | ops->func_hash = &ops->local_hash; | |
f04f24fb MH |
153 | ops->flags |= FTRACE_OPS_FL_INITIALIZED; |
154 | } | |
155 | #endif | |
156 | } | |
157 | ||
ea701f11 SR |
158 | /** |
159 | * ftrace_nr_registered_ops - return number of ops registered | |
160 | * | |
161 | * Returns the number of ftrace_ops registered and tracing functions | |
162 | */ | |
163 | int ftrace_nr_registered_ops(void) | |
164 | { | |
165 | struct ftrace_ops *ops; | |
166 | int cnt = 0; | |
167 | ||
168 | mutex_lock(&ftrace_lock); | |
169 | ||
170 | for (ops = ftrace_ops_list; | |
171 | ops != &ftrace_list_end; ops = ops->next) | |
172 | cnt++; | |
173 | ||
174 | mutex_unlock(&ftrace_lock); | |
175 | ||
176 | return cnt; | |
177 | } | |
178 | ||
2f5f6ad9 | 179 | static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 180 | struct ftrace_ops *op, struct pt_regs *regs) |
df4fc315 | 181 | { |
345ddcc8 SRRH |
182 | struct trace_array *tr = op->private; |
183 | ||
184 | if (tr && this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid)) | |
df4fc315 SR |
185 | return; |
186 | ||
e3eea140 | 187 | op->saved_func(ip, parent_ip, op, regs); |
df4fc315 SR |
188 | } |
189 | ||
16444a8a | 190 | /** |
3d083395 | 191 | * clear_ftrace_function - reset the ftrace function |
16444a8a | 192 | * |
3d083395 SR |
193 | * This NULLs the ftrace function and in essence stops |
194 | * tracing. There may be lag | |
16444a8a | 195 | */ |
3d083395 | 196 | void clear_ftrace_function(void) |
16444a8a | 197 | { |
3d083395 SR |
198 | ftrace_trace_function = ftrace_stub; |
199 | } | |
200 | ||
ba27f2bc | 201 | static void per_cpu_ops_disable_all(struct ftrace_ops *ops) |
e248491a JO |
202 | { |
203 | int cpu; | |
204 | ||
205 | for_each_possible_cpu(cpu) | |
206 | *per_cpu_ptr(ops->disabled, cpu) = 1; | |
207 | } | |
208 | ||
ba27f2bc | 209 | static int per_cpu_ops_alloc(struct ftrace_ops *ops) |
e248491a JO |
210 | { |
211 | int __percpu *disabled; | |
212 | ||
ba27f2bc SRRH |
213 | if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_PER_CPU))) |
214 | return -EINVAL; | |
215 | ||
e248491a JO |
216 | disabled = alloc_percpu(int); |
217 | if (!disabled) | |
218 | return -ENOMEM; | |
219 | ||
220 | ops->disabled = disabled; | |
ba27f2bc | 221 | per_cpu_ops_disable_all(ops); |
e248491a JO |
222 | return 0; |
223 | } | |
224 | ||
405e1d83 SRRH |
225 | static void ftrace_sync(struct work_struct *work) |
226 | { | |
227 | /* | |
228 | * This function is just a stub to implement a hard force | |
229 | * of synchronize_sched(). This requires synchronizing | |
230 | * tasks even in userspace and idle. | |
231 | * | |
232 | * Yes, function tracing is rude. | |
233 | */ | |
234 | } | |
235 | ||
236 | static void ftrace_sync_ipi(void *data) | |
237 | { | |
238 | /* Probably not needed, but do it anyway */ | |
239 | smp_rmb(); | |
240 | } | |
241 | ||
23a8e844 SRRH |
242 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
243 | static void update_function_graph_func(void); | |
55577204 SRRH |
244 | |
245 | /* Both enabled by default (can be cleared by function_graph tracer flags */ | |
246 | static bool fgraph_sleep_time = true; | |
247 | static bool fgraph_graph_time = true; | |
248 | ||
23a8e844 SRRH |
249 | #else |
250 | static inline void update_function_graph_func(void) { } | |
251 | #endif | |
252 | ||
00ccbf2f SRRH |
253 | |
254 | static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops) | |
255 | { | |
256 | /* | |
ba27f2bc | 257 | * If this is a dynamic, RCU, or per CPU ops, or we force list func, |
00ccbf2f SRRH |
258 | * then it needs to call the list anyway. |
259 | */ | |
ba27f2bc SRRH |
260 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU | |
261 | FTRACE_OPS_FL_RCU) || FTRACE_FORCE_LIST_FUNC) | |
00ccbf2f SRRH |
262 | return ftrace_ops_list_func; |
263 | ||
264 | return ftrace_ops_get_func(ops); | |
265 | } | |
266 | ||
2b499381 SR |
267 | static void update_ftrace_function(void) |
268 | { | |
269 | ftrace_func_t func; | |
270 | ||
f7aad4e1 SRRH |
271 | /* |
272 | * Prepare the ftrace_ops that the arch callback will use. | |
273 | * If there's only one ftrace_ops registered, the ftrace_ops_list | |
274 | * will point to the ops we want. | |
275 | */ | |
276 | set_function_trace_op = ftrace_ops_list; | |
277 | ||
278 | /* If there's no ftrace_ops registered, just call the stub function */ | |
279 | if (ftrace_ops_list == &ftrace_list_end) { | |
280 | func = ftrace_stub; | |
281 | ||
cdbe61bf SR |
282 | /* |
283 | * If we are at the end of the list and this ops is | |
4740974a SR |
284 | * recursion safe and not dynamic and the arch supports passing ops, |
285 | * then have the mcount trampoline call the function directly. | |
cdbe61bf | 286 | */ |
f7aad4e1 | 287 | } else if (ftrace_ops_list->next == &ftrace_list_end) { |
00ccbf2f | 288 | func = ftrace_ops_get_list_func(ftrace_ops_list); |
f7aad4e1 | 289 | |
2f5f6ad9 SR |
290 | } else { |
291 | /* Just use the default ftrace_ops */ | |
405e1d83 | 292 | set_function_trace_op = &ftrace_list_end; |
b848914c | 293 | func = ftrace_ops_list_func; |
2f5f6ad9 | 294 | } |
2b499381 | 295 | |
5f8bf2d2 SRRH |
296 | update_function_graph_func(); |
297 | ||
405e1d83 SRRH |
298 | /* If there's no change, then do nothing more here */ |
299 | if (ftrace_trace_function == func) | |
300 | return; | |
301 | ||
302 | /* | |
303 | * If we are using the list function, it doesn't care | |
304 | * about the function_trace_ops. | |
305 | */ | |
306 | if (func == ftrace_ops_list_func) { | |
307 | ftrace_trace_function = func; | |
308 | /* | |
309 | * Don't even bother setting function_trace_ops, | |
310 | * it would be racy to do so anyway. | |
311 | */ | |
312 | return; | |
313 | } | |
314 | ||
315 | #ifndef CONFIG_DYNAMIC_FTRACE | |
316 | /* | |
317 | * For static tracing, we need to be a bit more careful. | |
318 | * The function change takes affect immediately. Thus, | |
319 | * we need to coorditate the setting of the function_trace_ops | |
320 | * with the setting of the ftrace_trace_function. | |
321 | * | |
322 | * Set the function to the list ops, which will call the | |
323 | * function we want, albeit indirectly, but it handles the | |
324 | * ftrace_ops and doesn't depend on function_trace_op. | |
325 | */ | |
326 | ftrace_trace_function = ftrace_ops_list_func; | |
327 | /* | |
328 | * Make sure all CPUs see this. Yes this is slow, but static | |
329 | * tracing is slow and nasty to have enabled. | |
330 | */ | |
331 | schedule_on_each_cpu(ftrace_sync); | |
332 | /* Now all cpus are using the list ops. */ | |
333 | function_trace_op = set_function_trace_op; | |
334 | /* Make sure the function_trace_op is visible on all CPUs */ | |
335 | smp_wmb(); | |
336 | /* Nasty way to force a rmb on all cpus */ | |
337 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
338 | /* OK, we are all set to update the ftrace_trace_function now! */ | |
339 | #endif /* !CONFIG_DYNAMIC_FTRACE */ | |
340 | ||
491d0dcf | 341 | ftrace_trace_function = func; |
491d0dcf SR |
342 | } |
343 | ||
7eea4fce JW |
344 | int using_ftrace_ops_list_func(void) |
345 | { | |
346 | return ftrace_trace_function == ftrace_ops_list_func; | |
347 | } | |
348 | ||
2b499381 | 349 | static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
3d083395 | 350 | { |
2b499381 | 351 | ops->next = *list; |
16444a8a | 352 | /* |
b848914c | 353 | * We are entering ops into the list but another |
16444a8a ACM |
354 | * CPU might be walking that list. We need to make sure |
355 | * the ops->next pointer is valid before another CPU sees | |
b848914c | 356 | * the ops pointer included into the list. |
16444a8a | 357 | */ |
2b499381 | 358 | rcu_assign_pointer(*list, ops); |
16444a8a ACM |
359 | } |
360 | ||
2b499381 | 361 | static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) |
16444a8a | 362 | { |
16444a8a | 363 | struct ftrace_ops **p; |
16444a8a ACM |
364 | |
365 | /* | |
3d083395 SR |
366 | * If we are removing the last function, then simply point |
367 | * to the ftrace_stub. | |
16444a8a | 368 | */ |
2b499381 SR |
369 | if (*list == ops && ops->next == &ftrace_list_end) { |
370 | *list = &ftrace_list_end; | |
e6ea44e9 | 371 | return 0; |
16444a8a ACM |
372 | } |
373 | ||
2b499381 | 374 | for (p = list; *p != &ftrace_list_end; p = &(*p)->next) |
16444a8a ACM |
375 | if (*p == ops) |
376 | break; | |
377 | ||
e6ea44e9 SR |
378 | if (*p != ops) |
379 | return -1; | |
16444a8a ACM |
380 | |
381 | *p = (*p)->next; | |
2b499381 SR |
382 | return 0; |
383 | } | |
16444a8a | 384 | |
f3bea491 SRRH |
385 | static void ftrace_update_trampoline(struct ftrace_ops *ops); |
386 | ||
2b499381 SR |
387 | static int __register_ftrace_function(struct ftrace_ops *ops) |
388 | { | |
591dffda SRRH |
389 | if (ops->flags & FTRACE_OPS_FL_DELETED) |
390 | return -EINVAL; | |
391 | ||
b848914c SR |
392 | if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED)) |
393 | return -EBUSY; | |
394 | ||
06aeaaea | 395 | #ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
08f6fba5 SR |
396 | /* |
397 | * If the ftrace_ops specifies SAVE_REGS, then it only can be used | |
398 | * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set. | |
399 | * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant. | |
400 | */ | |
401 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS && | |
402 | !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)) | |
403 | return -EINVAL; | |
404 | ||
405 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED) | |
406 | ops->flags |= FTRACE_OPS_FL_SAVE_REGS; | |
407 | #endif | |
408 | ||
cdbe61bf SR |
409 | if (!core_kernel_data((unsigned long)ops)) |
410 | ops->flags |= FTRACE_OPS_FL_DYNAMIC; | |
411 | ||
ba27f2bc SRRH |
412 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) { |
413 | if (per_cpu_ops_alloc(ops)) | |
e248491a | 414 | return -ENOMEM; |
ba27f2bc SRRH |
415 | } |
416 | ||
417 | add_ftrace_ops(&ftrace_ops_list, ops); | |
b848914c | 418 | |
e3eea140 SRRH |
419 | /* Always save the function, and reset at unregistering */ |
420 | ops->saved_func = ops->func; | |
421 | ||
345ddcc8 | 422 | if (ftrace_pids_enabled(ops)) |
e3eea140 SRRH |
423 | ops->func = ftrace_pid_func; |
424 | ||
f3bea491 SRRH |
425 | ftrace_update_trampoline(ops); |
426 | ||
2b499381 SR |
427 | if (ftrace_enabled) |
428 | update_ftrace_function(); | |
429 | ||
430 | return 0; | |
431 | } | |
432 | ||
433 | static int __unregister_ftrace_function(struct ftrace_ops *ops) | |
434 | { | |
435 | int ret; | |
436 | ||
b848914c SR |
437 | if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED))) |
438 | return -EBUSY; | |
439 | ||
ba27f2bc | 440 | ret = remove_ftrace_ops(&ftrace_ops_list, ops); |
b848914c | 441 | |
2b499381 SR |
442 | if (ret < 0) |
443 | return ret; | |
b848914c | 444 | |
491d0dcf SR |
445 | if (ftrace_enabled) |
446 | update_ftrace_function(); | |
16444a8a | 447 | |
e3eea140 SRRH |
448 | ops->func = ops->saved_func; |
449 | ||
e6ea44e9 | 450 | return 0; |
3d083395 SR |
451 | } |
452 | ||
df4fc315 SR |
453 | static void ftrace_update_pid_func(void) |
454 | { | |
e3eea140 SRRH |
455 | struct ftrace_ops *op; |
456 | ||
491d0dcf | 457 | /* Only do something if we are tracing something */ |
df4fc315 | 458 | if (ftrace_trace_function == ftrace_stub) |
10dd3ebe | 459 | return; |
df4fc315 | 460 | |
e3eea140 SRRH |
461 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
462 | if (op->flags & FTRACE_OPS_FL_PID) { | |
345ddcc8 SRRH |
463 | op->func = ftrace_pids_enabled(op) ? |
464 | ftrace_pid_func : op->saved_func; | |
e3eea140 SRRH |
465 | ftrace_update_trampoline(op); |
466 | } | |
467 | } while_for_each_ftrace_op(op); | |
468 | ||
491d0dcf | 469 | update_ftrace_function(); |
df4fc315 SR |
470 | } |
471 | ||
493762fc SR |
472 | #ifdef CONFIG_FUNCTION_PROFILER |
473 | struct ftrace_profile { | |
474 | struct hlist_node node; | |
475 | unsigned long ip; | |
476 | unsigned long counter; | |
0706f1c4 SR |
477 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
478 | unsigned long long time; | |
e330b3bc | 479 | unsigned long long time_squared; |
0706f1c4 | 480 | #endif |
8fc0c701 SR |
481 | }; |
482 | ||
493762fc SR |
483 | struct ftrace_profile_page { |
484 | struct ftrace_profile_page *next; | |
485 | unsigned long index; | |
486 | struct ftrace_profile records[]; | |
d61f82d0 SR |
487 | }; |
488 | ||
cafb168a SR |
489 | struct ftrace_profile_stat { |
490 | atomic_t disabled; | |
491 | struct hlist_head *hash; | |
492 | struct ftrace_profile_page *pages; | |
493 | struct ftrace_profile_page *start; | |
494 | struct tracer_stat stat; | |
495 | }; | |
496 | ||
493762fc SR |
497 | #define PROFILE_RECORDS_SIZE \ |
498 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | |
5072c59f | 499 | |
493762fc SR |
500 | #define PROFILES_PER_PAGE \ |
501 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | |
3d083395 | 502 | |
fb9fb015 SR |
503 | static int ftrace_profile_enabled __read_mostly; |
504 | ||
505 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | |
bac429f0 SR |
506 | static DEFINE_MUTEX(ftrace_profile_lock); |
507 | ||
cafb168a | 508 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); |
493762fc | 509 | |
20079ebe NK |
510 | #define FTRACE_PROFILE_HASH_BITS 10 |
511 | #define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS) | |
493762fc | 512 | |
bac429f0 SR |
513 | static void * |
514 | function_stat_next(void *v, int idx) | |
515 | { | |
493762fc SR |
516 | struct ftrace_profile *rec = v; |
517 | struct ftrace_profile_page *pg; | |
bac429f0 | 518 | |
493762fc | 519 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); |
bac429f0 SR |
520 | |
521 | again: | |
0296e425 LZ |
522 | if (idx != 0) |
523 | rec++; | |
524 | ||
bac429f0 SR |
525 | if ((void *)rec >= (void *)&pg->records[pg->index]) { |
526 | pg = pg->next; | |
527 | if (!pg) | |
528 | return NULL; | |
529 | rec = &pg->records[0]; | |
493762fc SR |
530 | if (!rec->counter) |
531 | goto again; | |
bac429f0 SR |
532 | } |
533 | ||
bac429f0 SR |
534 | return rec; |
535 | } | |
536 | ||
537 | static void *function_stat_start(struct tracer_stat *trace) | |
538 | { | |
cafb168a SR |
539 | struct ftrace_profile_stat *stat = |
540 | container_of(trace, struct ftrace_profile_stat, stat); | |
541 | ||
542 | if (!stat || !stat->start) | |
543 | return NULL; | |
544 | ||
545 | return function_stat_next(&stat->start->records[0], 0); | |
bac429f0 SR |
546 | } |
547 | ||
0706f1c4 SR |
548 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
549 | /* function graph compares on total time */ | |
550 | static int function_stat_cmp(void *p1, void *p2) | |
551 | { | |
552 | struct ftrace_profile *a = p1; | |
553 | struct ftrace_profile *b = p2; | |
554 | ||
555 | if (a->time < b->time) | |
556 | return -1; | |
557 | if (a->time > b->time) | |
558 | return 1; | |
559 | else | |
560 | return 0; | |
561 | } | |
562 | #else | |
563 | /* not function graph compares against hits */ | |
bac429f0 SR |
564 | static int function_stat_cmp(void *p1, void *p2) |
565 | { | |
493762fc SR |
566 | struct ftrace_profile *a = p1; |
567 | struct ftrace_profile *b = p2; | |
bac429f0 SR |
568 | |
569 | if (a->counter < b->counter) | |
570 | return -1; | |
571 | if (a->counter > b->counter) | |
572 | return 1; | |
573 | else | |
574 | return 0; | |
575 | } | |
0706f1c4 | 576 | #endif |
bac429f0 SR |
577 | |
578 | static int function_stat_headers(struct seq_file *m) | |
579 | { | |
0706f1c4 | 580 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
fa6f0cc7 RV |
581 | seq_puts(m, " Function " |
582 | "Hit Time Avg s^2\n" | |
583 | " -------- " | |
584 | "--- ---- --- ---\n"); | |
0706f1c4 | 585 | #else |
fa6f0cc7 RV |
586 | seq_puts(m, " Function Hit\n" |
587 | " -------- ---\n"); | |
0706f1c4 | 588 | #endif |
bac429f0 SR |
589 | return 0; |
590 | } | |
591 | ||
592 | static int function_stat_show(struct seq_file *m, void *v) | |
593 | { | |
493762fc | 594 | struct ftrace_profile *rec = v; |
bac429f0 | 595 | char str[KSYM_SYMBOL_LEN]; |
3aaba20f | 596 | int ret = 0; |
0706f1c4 | 597 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
34886c8b SR |
598 | static struct trace_seq s; |
599 | unsigned long long avg; | |
e330b3bc | 600 | unsigned long long stddev; |
0706f1c4 | 601 | #endif |
3aaba20f LZ |
602 | mutex_lock(&ftrace_profile_lock); |
603 | ||
604 | /* we raced with function_profile_reset() */ | |
605 | if (unlikely(rec->counter == 0)) { | |
606 | ret = -EBUSY; | |
607 | goto out; | |
608 | } | |
bac429f0 | 609 | |
8e436ca0 UT |
610 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
611 | avg = rec->time; | |
612 | do_div(avg, rec->counter); | |
613 | if (tracing_thresh && (avg < tracing_thresh)) | |
614 | goto out; | |
615 | #endif | |
616 | ||
bac429f0 | 617 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); |
0706f1c4 SR |
618 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); |
619 | ||
620 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
fa6f0cc7 | 621 | seq_puts(m, " "); |
34886c8b | 622 | |
e330b3bc CD |
623 | /* Sample standard deviation (s^2) */ |
624 | if (rec->counter <= 1) | |
625 | stddev = 0; | |
626 | else { | |
52d85d76 JL |
627 | /* |
628 | * Apply Welford's method: | |
629 | * s^2 = 1 / (n * (n-1)) * (n * \Sum (x_i)^2 - (\Sum x_i)^2) | |
630 | */ | |
631 | stddev = rec->counter * rec->time_squared - | |
632 | rec->time * rec->time; | |
633 | ||
e330b3bc CD |
634 | /* |
635 | * Divide only 1000 for ns^2 -> us^2 conversion. | |
636 | * trace_print_graph_duration will divide 1000 again. | |
637 | */ | |
52d85d76 | 638 | do_div(stddev, rec->counter * (rec->counter - 1) * 1000); |
e330b3bc CD |
639 | } |
640 | ||
34886c8b SR |
641 | trace_seq_init(&s); |
642 | trace_print_graph_duration(rec->time, &s); | |
643 | trace_seq_puts(&s, " "); | |
644 | trace_print_graph_duration(avg, &s); | |
e330b3bc CD |
645 | trace_seq_puts(&s, " "); |
646 | trace_print_graph_duration(stddev, &s); | |
0706f1c4 | 647 | trace_print_seq(m, &s); |
0706f1c4 SR |
648 | #endif |
649 | seq_putc(m, '\n'); | |
3aaba20f LZ |
650 | out: |
651 | mutex_unlock(&ftrace_profile_lock); | |
bac429f0 | 652 | |
3aaba20f | 653 | return ret; |
bac429f0 SR |
654 | } |
655 | ||
cafb168a | 656 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) |
bac429f0 | 657 | { |
493762fc | 658 | struct ftrace_profile_page *pg; |
bac429f0 | 659 | |
cafb168a | 660 | pg = stat->pages = stat->start; |
bac429f0 | 661 | |
493762fc SR |
662 | while (pg) { |
663 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | |
664 | pg->index = 0; | |
665 | pg = pg->next; | |
bac429f0 SR |
666 | } |
667 | ||
cafb168a | 668 | memset(stat->hash, 0, |
493762fc SR |
669 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); |
670 | } | |
bac429f0 | 671 | |
cafb168a | 672 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) |
493762fc SR |
673 | { |
674 | struct ftrace_profile_page *pg; | |
318e0a73 SR |
675 | int functions; |
676 | int pages; | |
493762fc | 677 | int i; |
bac429f0 | 678 | |
493762fc | 679 | /* If we already allocated, do nothing */ |
cafb168a | 680 | if (stat->pages) |
493762fc | 681 | return 0; |
bac429f0 | 682 | |
cafb168a SR |
683 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); |
684 | if (!stat->pages) | |
493762fc | 685 | return -ENOMEM; |
bac429f0 | 686 | |
318e0a73 SR |
687 | #ifdef CONFIG_DYNAMIC_FTRACE |
688 | functions = ftrace_update_tot_cnt; | |
689 | #else | |
690 | /* | |
691 | * We do not know the number of functions that exist because | |
692 | * dynamic tracing is what counts them. With past experience | |
693 | * we have around 20K functions. That should be more than enough. | |
694 | * It is highly unlikely we will execute every function in | |
695 | * the kernel. | |
696 | */ | |
697 | functions = 20000; | |
698 | #endif | |
699 | ||
cafb168a | 700 | pg = stat->start = stat->pages; |
bac429f0 | 701 | |
318e0a73 SR |
702 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); |
703 | ||
39e30cd1 | 704 | for (i = 1; i < pages; i++) { |
493762fc | 705 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); |
493762fc | 706 | if (!pg->next) |
318e0a73 | 707 | goto out_free; |
493762fc SR |
708 | pg = pg->next; |
709 | } | |
710 | ||
711 | return 0; | |
318e0a73 SR |
712 | |
713 | out_free: | |
714 | pg = stat->start; | |
715 | while (pg) { | |
716 | unsigned long tmp = (unsigned long)pg; | |
717 | ||
718 | pg = pg->next; | |
719 | free_page(tmp); | |
720 | } | |
721 | ||
318e0a73 SR |
722 | stat->pages = NULL; |
723 | stat->start = NULL; | |
724 | ||
725 | return -ENOMEM; | |
bac429f0 SR |
726 | } |
727 | ||
cafb168a | 728 | static int ftrace_profile_init_cpu(int cpu) |
bac429f0 | 729 | { |
cafb168a | 730 | struct ftrace_profile_stat *stat; |
493762fc | 731 | int size; |
bac429f0 | 732 | |
cafb168a SR |
733 | stat = &per_cpu(ftrace_profile_stats, cpu); |
734 | ||
735 | if (stat->hash) { | |
493762fc | 736 | /* If the profile is already created, simply reset it */ |
cafb168a | 737 | ftrace_profile_reset(stat); |
493762fc SR |
738 | return 0; |
739 | } | |
bac429f0 | 740 | |
493762fc SR |
741 | /* |
742 | * We are profiling all functions, but usually only a few thousand | |
743 | * functions are hit. We'll make a hash of 1024 items. | |
744 | */ | |
745 | size = FTRACE_PROFILE_HASH_SIZE; | |
bac429f0 | 746 | |
cafb168a | 747 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); |
493762fc | 748 | |
cafb168a | 749 | if (!stat->hash) |
493762fc SR |
750 | return -ENOMEM; |
751 | ||
318e0a73 | 752 | /* Preallocate the function profiling pages */ |
cafb168a SR |
753 | if (ftrace_profile_pages_init(stat) < 0) { |
754 | kfree(stat->hash); | |
755 | stat->hash = NULL; | |
493762fc SR |
756 | return -ENOMEM; |
757 | } | |
758 | ||
759 | return 0; | |
bac429f0 SR |
760 | } |
761 | ||
cafb168a SR |
762 | static int ftrace_profile_init(void) |
763 | { | |
764 | int cpu; | |
765 | int ret = 0; | |
766 | ||
c4602c1c | 767 | for_each_possible_cpu(cpu) { |
cafb168a SR |
768 | ret = ftrace_profile_init_cpu(cpu); |
769 | if (ret) | |
770 | break; | |
771 | } | |
772 | ||
773 | return ret; | |
774 | } | |
775 | ||
493762fc | 776 | /* interrupts must be disabled */ |
cafb168a SR |
777 | static struct ftrace_profile * |
778 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | |
bac429f0 | 779 | { |
493762fc | 780 | struct ftrace_profile *rec; |
bac429f0 | 781 | struct hlist_head *hhd; |
bac429f0 SR |
782 | unsigned long key; |
783 | ||
20079ebe | 784 | key = hash_long(ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 785 | hhd = &stat->hash[key]; |
bac429f0 SR |
786 | |
787 | if (hlist_empty(hhd)) | |
788 | return NULL; | |
789 | ||
1bb539ca | 790 | hlist_for_each_entry_rcu_notrace(rec, hhd, node) { |
bac429f0 | 791 | if (rec->ip == ip) |
493762fc SR |
792 | return rec; |
793 | } | |
794 | ||
795 | return NULL; | |
796 | } | |
797 | ||
cafb168a SR |
798 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, |
799 | struct ftrace_profile *rec) | |
493762fc SR |
800 | { |
801 | unsigned long key; | |
802 | ||
20079ebe | 803 | key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS); |
cafb168a | 804 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); |
493762fc SR |
805 | } |
806 | ||
318e0a73 SR |
807 | /* |
808 | * The memory is already allocated, this simply finds a new record to use. | |
809 | */ | |
493762fc | 810 | static struct ftrace_profile * |
318e0a73 | 811 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) |
493762fc SR |
812 | { |
813 | struct ftrace_profile *rec = NULL; | |
814 | ||
318e0a73 | 815 | /* prevent recursion (from NMIs) */ |
cafb168a | 816 | if (atomic_inc_return(&stat->disabled) != 1) |
493762fc SR |
817 | goto out; |
818 | ||
493762fc | 819 | /* |
318e0a73 SR |
820 | * Try to find the function again since an NMI |
821 | * could have added it | |
493762fc | 822 | */ |
cafb168a | 823 | rec = ftrace_find_profiled_func(stat, ip); |
493762fc | 824 | if (rec) |
cafb168a | 825 | goto out; |
493762fc | 826 | |
cafb168a SR |
827 | if (stat->pages->index == PROFILES_PER_PAGE) { |
828 | if (!stat->pages->next) | |
829 | goto out; | |
830 | stat->pages = stat->pages->next; | |
bac429f0 | 831 | } |
493762fc | 832 | |
cafb168a | 833 | rec = &stat->pages->records[stat->pages->index++]; |
493762fc | 834 | rec->ip = ip; |
cafb168a | 835 | ftrace_add_profile(stat, rec); |
493762fc | 836 | |
bac429f0 | 837 | out: |
cafb168a | 838 | atomic_dec(&stat->disabled); |
bac429f0 SR |
839 | |
840 | return rec; | |
841 | } | |
842 | ||
843 | static void | |
2f5f6ad9 | 844 | function_profile_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 845 | struct ftrace_ops *ops, struct pt_regs *regs) |
bac429f0 | 846 | { |
cafb168a | 847 | struct ftrace_profile_stat *stat; |
493762fc | 848 | struct ftrace_profile *rec; |
bac429f0 SR |
849 | unsigned long flags; |
850 | ||
851 | if (!ftrace_profile_enabled) | |
852 | return; | |
853 | ||
854 | local_irq_save(flags); | |
cafb168a | 855 | |
bdffd893 | 856 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 857 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
858 | goto out; |
859 | ||
860 | rec = ftrace_find_profiled_func(stat, ip); | |
493762fc | 861 | if (!rec) { |
318e0a73 | 862 | rec = ftrace_profile_alloc(stat, ip); |
493762fc SR |
863 | if (!rec) |
864 | goto out; | |
865 | } | |
bac429f0 SR |
866 | |
867 | rec->counter++; | |
868 | out: | |
869 | local_irq_restore(flags); | |
870 | } | |
871 | ||
0706f1c4 SR |
872 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
873 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | |
874 | { | |
8861dd30 NK |
875 | int index = trace->depth; |
876 | ||
a1e2e31d | 877 | function_profile_call(trace->func, 0, NULL, NULL); |
8861dd30 NK |
878 | |
879 | if (index >= 0 && index < FTRACE_RETFUNC_DEPTH) | |
880 | current->ret_stack[index].subtime = 0; | |
881 | ||
0706f1c4 SR |
882 | return 1; |
883 | } | |
884 | ||
885 | static void profile_graph_return(struct ftrace_graph_ret *trace) | |
886 | { | |
cafb168a | 887 | struct ftrace_profile_stat *stat; |
a2a16d6a | 888 | unsigned long long calltime; |
0706f1c4 | 889 | struct ftrace_profile *rec; |
cafb168a | 890 | unsigned long flags; |
0706f1c4 SR |
891 | |
892 | local_irq_save(flags); | |
bdffd893 | 893 | stat = this_cpu_ptr(&ftrace_profile_stats); |
0f6ce3de | 894 | if (!stat->hash || !ftrace_profile_enabled) |
cafb168a SR |
895 | goto out; |
896 | ||
37e44bc5 SR |
897 | /* If the calltime was zero'd ignore it */ |
898 | if (!trace->calltime) | |
899 | goto out; | |
900 | ||
a2a16d6a SR |
901 | calltime = trace->rettime - trace->calltime; |
902 | ||
55577204 | 903 | if (!fgraph_graph_time) { |
a2a16d6a SR |
904 | int index; |
905 | ||
906 | index = trace->depth; | |
907 | ||
908 | /* Append this call time to the parent time to subtract */ | |
909 | if (index) | |
910 | current->ret_stack[index - 1].subtime += calltime; | |
911 | ||
912 | if (current->ret_stack[index].subtime < calltime) | |
913 | calltime -= current->ret_stack[index].subtime; | |
914 | else | |
915 | calltime = 0; | |
916 | } | |
917 | ||
cafb168a | 918 | rec = ftrace_find_profiled_func(stat, trace->func); |
e330b3bc | 919 | if (rec) { |
a2a16d6a | 920 | rec->time += calltime; |
e330b3bc CD |
921 | rec->time_squared += calltime * calltime; |
922 | } | |
a2a16d6a | 923 | |
cafb168a | 924 | out: |
0706f1c4 SR |
925 | local_irq_restore(flags); |
926 | } | |
927 | ||
928 | static int register_ftrace_profiler(void) | |
929 | { | |
930 | return register_ftrace_graph(&profile_graph_return, | |
931 | &profile_graph_entry); | |
932 | } | |
933 | ||
934 | static void unregister_ftrace_profiler(void) | |
935 | { | |
936 | unregister_ftrace_graph(); | |
937 | } | |
938 | #else | |
bd38c0e6 | 939 | static struct ftrace_ops ftrace_profile_ops __read_mostly = { |
fb9fb015 | 940 | .func = function_profile_call, |
f04f24fb | 941 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 942 | INIT_OPS_HASH(ftrace_profile_ops) |
bac429f0 SR |
943 | }; |
944 | ||
0706f1c4 SR |
945 | static int register_ftrace_profiler(void) |
946 | { | |
947 | return register_ftrace_function(&ftrace_profile_ops); | |
948 | } | |
949 | ||
950 | static void unregister_ftrace_profiler(void) | |
951 | { | |
952 | unregister_ftrace_function(&ftrace_profile_ops); | |
953 | } | |
954 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
955 | ||
bac429f0 SR |
956 | static ssize_t |
957 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | |
958 | size_t cnt, loff_t *ppos) | |
959 | { | |
960 | unsigned long val; | |
bac429f0 SR |
961 | int ret; |
962 | ||
22fe9b54 PH |
963 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
964 | if (ret) | |
bac429f0 SR |
965 | return ret; |
966 | ||
967 | val = !!val; | |
968 | ||
969 | mutex_lock(&ftrace_profile_lock); | |
970 | if (ftrace_profile_enabled ^ val) { | |
971 | if (val) { | |
493762fc SR |
972 | ret = ftrace_profile_init(); |
973 | if (ret < 0) { | |
974 | cnt = ret; | |
975 | goto out; | |
976 | } | |
977 | ||
0706f1c4 SR |
978 | ret = register_ftrace_profiler(); |
979 | if (ret < 0) { | |
980 | cnt = ret; | |
981 | goto out; | |
982 | } | |
bac429f0 SR |
983 | ftrace_profile_enabled = 1; |
984 | } else { | |
985 | ftrace_profile_enabled = 0; | |
0f6ce3de SR |
986 | /* |
987 | * unregister_ftrace_profiler calls stop_machine | |
988 | * so this acts like an synchronize_sched. | |
989 | */ | |
0706f1c4 | 990 | unregister_ftrace_profiler(); |
bac429f0 SR |
991 | } |
992 | } | |
493762fc | 993 | out: |
bac429f0 SR |
994 | mutex_unlock(&ftrace_profile_lock); |
995 | ||
cf8517cf | 996 | *ppos += cnt; |
bac429f0 SR |
997 | |
998 | return cnt; | |
999 | } | |
1000 | ||
493762fc SR |
1001 | static ssize_t |
1002 | ftrace_profile_read(struct file *filp, char __user *ubuf, | |
1003 | size_t cnt, loff_t *ppos) | |
1004 | { | |
fb9fb015 | 1005 | char buf[64]; /* big enough to hold a number */ |
493762fc SR |
1006 | int r; |
1007 | ||
1008 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | |
1009 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
1010 | } | |
1011 | ||
bac429f0 SR |
1012 | static const struct file_operations ftrace_profile_fops = { |
1013 | .open = tracing_open_generic, | |
1014 | .read = ftrace_profile_read, | |
1015 | .write = ftrace_profile_write, | |
6038f373 | 1016 | .llseek = default_llseek, |
bac429f0 SR |
1017 | }; |
1018 | ||
cafb168a SR |
1019 | /* used to initialize the real stat files */ |
1020 | static struct tracer_stat function_stats __initdata = { | |
fb9fb015 SR |
1021 | .name = "functions", |
1022 | .stat_start = function_stat_start, | |
1023 | .stat_next = function_stat_next, | |
1024 | .stat_cmp = function_stat_cmp, | |
1025 | .stat_headers = function_stat_headers, | |
1026 | .stat_show = function_stat_show | |
cafb168a SR |
1027 | }; |
1028 | ||
8434dc93 | 1029 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 | 1030 | { |
cafb168a | 1031 | struct ftrace_profile_stat *stat; |
bac429f0 | 1032 | struct dentry *entry; |
cafb168a | 1033 | char *name; |
bac429f0 | 1034 | int ret; |
cafb168a SR |
1035 | int cpu; |
1036 | ||
1037 | for_each_possible_cpu(cpu) { | |
1038 | stat = &per_cpu(ftrace_profile_stats, cpu); | |
1039 | ||
6363c6b5 | 1040 | name = kasprintf(GFP_KERNEL, "function%d", cpu); |
cafb168a SR |
1041 | if (!name) { |
1042 | /* | |
1043 | * The files created are permanent, if something happens | |
1044 | * we still do not free memory. | |
1045 | */ | |
cafb168a SR |
1046 | WARN(1, |
1047 | "Could not allocate stat file for cpu %d\n", | |
1048 | cpu); | |
1049 | return; | |
1050 | } | |
1051 | stat->stat = function_stats; | |
cafb168a SR |
1052 | stat->stat.name = name; |
1053 | ret = register_stat_tracer(&stat->stat); | |
1054 | if (ret) { | |
1055 | WARN(1, | |
1056 | "Could not register function stat for cpu %d\n", | |
1057 | cpu); | |
1058 | kfree(name); | |
1059 | return; | |
1060 | } | |
bac429f0 SR |
1061 | } |
1062 | ||
8434dc93 | 1063 | entry = tracefs_create_file("function_profile_enabled", 0644, |
bac429f0 SR |
1064 | d_tracer, NULL, &ftrace_profile_fops); |
1065 | if (!entry) | |
a395d6a7 | 1066 | pr_warn("Could not create tracefs 'function_profile_enabled' entry\n"); |
bac429f0 SR |
1067 | } |
1068 | ||
bac429f0 | 1069 | #else /* CONFIG_FUNCTION_PROFILER */ |
8434dc93 | 1070 | static __init void ftrace_profile_tracefs(struct dentry *d_tracer) |
bac429f0 SR |
1071 | { |
1072 | } | |
bac429f0 SR |
1073 | #endif /* CONFIG_FUNCTION_PROFILER */ |
1074 | ||
493762fc SR |
1075 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
1076 | ||
1619dc3f PA |
1077 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
1078 | static int ftrace_graph_active; | |
1079 | #else | |
1080 | # define ftrace_graph_active 0 | |
1081 | #endif | |
1082 | ||
493762fc SR |
1083 | #ifdef CONFIG_DYNAMIC_FTRACE |
1084 | ||
79922b80 SRRH |
1085 | static struct ftrace_ops *removed_ops; |
1086 | ||
e1effa01 SRRH |
1087 | /* |
1088 | * Set when doing a global update, like enabling all recs or disabling them. | |
1089 | * It is not set when just updating a single ftrace_ops. | |
1090 | */ | |
1091 | static bool update_all_ops; | |
1092 | ||
493762fc SR |
1093 | #ifndef CONFIG_FTRACE_MCOUNT_RECORD |
1094 | # error Dynamic ftrace depends on MCOUNT_RECORD | |
1095 | #endif | |
1096 | ||
1097 | static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly; | |
1098 | ||
1099 | struct ftrace_func_probe { | |
1100 | struct hlist_node node; | |
1101 | struct ftrace_probe_ops *ops; | |
1102 | unsigned long flags; | |
1103 | unsigned long ip; | |
1104 | void *data; | |
7818b388 | 1105 | struct list_head free_list; |
493762fc SR |
1106 | }; |
1107 | ||
b448c4e3 SR |
1108 | struct ftrace_func_entry { |
1109 | struct hlist_node hlist; | |
1110 | unsigned long ip; | |
1111 | }; | |
1112 | ||
33dc9b12 SR |
1113 | /* |
1114 | * We make these constant because no one should touch them, | |
1115 | * but they are used as the default "empty hash", to avoid allocating | |
1116 | * it all the time. These are in a read only section such that if | |
1117 | * anyone does try to modify it, it will cause an exception. | |
1118 | */ | |
1119 | static const struct hlist_head empty_buckets[1]; | |
1120 | static const struct ftrace_hash empty_hash = { | |
1121 | .buckets = (struct hlist_head *)empty_buckets, | |
1cf41dd7 | 1122 | }; |
33dc9b12 | 1123 | #define EMPTY_HASH ((struct ftrace_hash *)&empty_hash) |
493762fc | 1124 | |
2b499381 | 1125 | static struct ftrace_ops global_ops = { |
33b7f99c SRRH |
1126 | .func = ftrace_stub, |
1127 | .local_hash.notrace_hash = EMPTY_HASH, | |
1128 | .local_hash.filter_hash = EMPTY_HASH, | |
1129 | INIT_OPS_HASH(global_ops) | |
1130 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
e3eea140 SRRH |
1131 | FTRACE_OPS_FL_INITIALIZED | |
1132 | FTRACE_OPS_FL_PID, | |
f45948e8 SR |
1133 | }; |
1134 | ||
aec0be2d SRRH |
1135 | /* |
1136 | * This is used by __kernel_text_address() to return true if the | |
0af26492 | 1137 | * address is on a dynamically allocated trampoline that would |
aec0be2d SRRH |
1138 | * not return true for either core_kernel_text() or |
1139 | * is_module_text_address(). | |
1140 | */ | |
1141 | bool is_ftrace_trampoline(unsigned long addr) | |
1142 | { | |
1143 | struct ftrace_ops *op; | |
1144 | bool ret = false; | |
1145 | ||
1146 | /* | |
1147 | * Some of the ops may be dynamically allocated, | |
1148 | * they are freed after a synchronize_sched(). | |
1149 | */ | |
1150 | preempt_disable_notrace(); | |
1151 | ||
1152 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1153 | /* | |
1154 | * This is to check for dynamically allocated trampolines. | |
1155 | * Trampolines that are in kernel text will have | |
1156 | * core_kernel_text() return true. | |
1157 | */ | |
1158 | if (op->trampoline && op->trampoline_size) | |
1159 | if (addr >= op->trampoline && | |
1160 | addr < op->trampoline + op->trampoline_size) { | |
1161 | ret = true; | |
1162 | goto out; | |
1163 | } | |
1164 | } while_for_each_ftrace_op(op); | |
1165 | ||
1166 | out: | |
1167 | preempt_enable_notrace(); | |
1168 | ||
1169 | return ret; | |
1170 | } | |
1171 | ||
493762fc SR |
1172 | struct ftrace_page { |
1173 | struct ftrace_page *next; | |
a7900875 | 1174 | struct dyn_ftrace *records; |
493762fc | 1175 | int index; |
a7900875 | 1176 | int size; |
493762fc SR |
1177 | }; |
1178 | ||
a7900875 SR |
1179 | #define ENTRY_SIZE sizeof(struct dyn_ftrace) |
1180 | #define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE) | |
493762fc SR |
1181 | |
1182 | /* estimate from running different kernels */ | |
1183 | #define NR_TO_INIT 10000 | |
1184 | ||
1185 | static struct ftrace_page *ftrace_pages_start; | |
1186 | static struct ftrace_page *ftrace_pages; | |
1187 | ||
2b0cce0e SRV |
1188 | static __always_inline unsigned long |
1189 | ftrace_hash_key(struct ftrace_hash *hash, unsigned long ip) | |
1190 | { | |
1191 | if (hash->size_bits > 0) | |
1192 | return hash_long(ip, hash->size_bits); | |
1193 | ||
1194 | return 0; | |
1195 | } | |
1196 | ||
2b2c279c SRV |
1197 | /* Only use this function if ftrace_hash_empty() has already been tested */ |
1198 | static __always_inline struct ftrace_func_entry * | |
1199 | __ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
b448c4e3 SR |
1200 | { |
1201 | unsigned long key; | |
1202 | struct ftrace_func_entry *entry; | |
1203 | struct hlist_head *hhd; | |
b448c4e3 | 1204 | |
2b0cce0e | 1205 | key = ftrace_hash_key(hash, ip); |
b448c4e3 SR |
1206 | hhd = &hash->buckets[key]; |
1207 | ||
1bb539ca | 1208 | hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) { |
b448c4e3 SR |
1209 | if (entry->ip == ip) |
1210 | return entry; | |
1211 | } | |
1212 | return NULL; | |
1213 | } | |
1214 | ||
2b2c279c SRV |
1215 | /** |
1216 | * ftrace_lookup_ip - Test to see if an ip exists in an ftrace_hash | |
1217 | * @hash: The hash to look at | |
1218 | * @ip: The instruction pointer to test | |
1219 | * | |
1220 | * Search a given @hash to see if a given instruction pointer (@ip) | |
1221 | * exists in it. | |
1222 | * | |
1223 | * Returns the entry that holds the @ip if found. NULL otherwise. | |
1224 | */ | |
1225 | struct ftrace_func_entry * | |
1226 | ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip) | |
1227 | { | |
1228 | if (ftrace_hash_empty(hash)) | |
1229 | return NULL; | |
1230 | ||
1231 | return __ftrace_lookup_ip(hash, ip); | |
1232 | } | |
1233 | ||
33dc9b12 SR |
1234 | static void __add_hash_entry(struct ftrace_hash *hash, |
1235 | struct ftrace_func_entry *entry) | |
b448c4e3 | 1236 | { |
b448c4e3 SR |
1237 | struct hlist_head *hhd; |
1238 | unsigned long key; | |
1239 | ||
2b0cce0e | 1240 | key = ftrace_hash_key(hash, entry->ip); |
b448c4e3 SR |
1241 | hhd = &hash->buckets[key]; |
1242 | hlist_add_head(&entry->hlist, hhd); | |
1243 | hash->count++; | |
33dc9b12 SR |
1244 | } |
1245 | ||
1246 | static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip) | |
1247 | { | |
1248 | struct ftrace_func_entry *entry; | |
1249 | ||
1250 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
1251 | if (!entry) | |
1252 | return -ENOMEM; | |
1253 | ||
1254 | entry->ip = ip; | |
1255 | __add_hash_entry(hash, entry); | |
b448c4e3 SR |
1256 | |
1257 | return 0; | |
1258 | } | |
1259 | ||
1260 | static void | |
33dc9b12 | 1261 | free_hash_entry(struct ftrace_hash *hash, |
b448c4e3 SR |
1262 | struct ftrace_func_entry *entry) |
1263 | { | |
1264 | hlist_del(&entry->hlist); | |
1265 | kfree(entry); | |
1266 | hash->count--; | |
1267 | } | |
1268 | ||
33dc9b12 SR |
1269 | static void |
1270 | remove_hash_entry(struct ftrace_hash *hash, | |
1271 | struct ftrace_func_entry *entry) | |
1272 | { | |
1273 | hlist_del(&entry->hlist); | |
1274 | hash->count--; | |
1275 | } | |
1276 | ||
b448c4e3 SR |
1277 | static void ftrace_hash_clear(struct ftrace_hash *hash) |
1278 | { | |
1279 | struct hlist_head *hhd; | |
b67bfe0d | 1280 | struct hlist_node *tn; |
b448c4e3 SR |
1281 | struct ftrace_func_entry *entry; |
1282 | int size = 1 << hash->size_bits; | |
1283 | int i; | |
1284 | ||
33dc9b12 SR |
1285 | if (!hash->count) |
1286 | return; | |
1287 | ||
b448c4e3 SR |
1288 | for (i = 0; i < size; i++) { |
1289 | hhd = &hash->buckets[i]; | |
b67bfe0d | 1290 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) |
33dc9b12 | 1291 | free_hash_entry(hash, entry); |
b448c4e3 SR |
1292 | } |
1293 | FTRACE_WARN_ON(hash->count); | |
1294 | } | |
1295 | ||
33dc9b12 SR |
1296 | static void free_ftrace_hash(struct ftrace_hash *hash) |
1297 | { | |
1298 | if (!hash || hash == EMPTY_HASH) | |
1299 | return; | |
1300 | ftrace_hash_clear(hash); | |
1301 | kfree(hash->buckets); | |
1302 | kfree(hash); | |
1303 | } | |
1304 | ||
07fd5515 SR |
1305 | static void __free_ftrace_hash_rcu(struct rcu_head *rcu) |
1306 | { | |
1307 | struct ftrace_hash *hash; | |
1308 | ||
1309 | hash = container_of(rcu, struct ftrace_hash, rcu); | |
1310 | free_ftrace_hash(hash); | |
1311 | } | |
1312 | ||
1313 | static void free_ftrace_hash_rcu(struct ftrace_hash *hash) | |
1314 | { | |
1315 | if (!hash || hash == EMPTY_HASH) | |
1316 | return; | |
1317 | call_rcu_sched(&hash->rcu, __free_ftrace_hash_rcu); | |
1318 | } | |
1319 | ||
5500fa51 JO |
1320 | void ftrace_free_filter(struct ftrace_ops *ops) |
1321 | { | |
f04f24fb | 1322 | ftrace_ops_init(ops); |
33b7f99c SRRH |
1323 | free_ftrace_hash(ops->func_hash->filter_hash); |
1324 | free_ftrace_hash(ops->func_hash->notrace_hash); | |
5500fa51 JO |
1325 | } |
1326 | ||
33dc9b12 SR |
1327 | static struct ftrace_hash *alloc_ftrace_hash(int size_bits) |
1328 | { | |
1329 | struct ftrace_hash *hash; | |
1330 | int size; | |
1331 | ||
1332 | hash = kzalloc(sizeof(*hash), GFP_KERNEL); | |
1333 | if (!hash) | |
1334 | return NULL; | |
1335 | ||
1336 | size = 1 << size_bits; | |
47b0edcb | 1337 | hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL); |
33dc9b12 SR |
1338 | |
1339 | if (!hash->buckets) { | |
1340 | kfree(hash); | |
1341 | return NULL; | |
1342 | } | |
1343 | ||
1344 | hash->size_bits = size_bits; | |
1345 | ||
1346 | return hash; | |
1347 | } | |
1348 | ||
1349 | static struct ftrace_hash * | |
1350 | alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) | |
1351 | { | |
1352 | struct ftrace_func_entry *entry; | |
1353 | struct ftrace_hash *new_hash; | |
33dc9b12 SR |
1354 | int size; |
1355 | int ret; | |
1356 | int i; | |
1357 | ||
1358 | new_hash = alloc_ftrace_hash(size_bits); | |
1359 | if (!new_hash) | |
1360 | return NULL; | |
1361 | ||
1362 | /* Empty hash? */ | |
06a51d93 | 1363 | if (ftrace_hash_empty(hash)) |
33dc9b12 SR |
1364 | return new_hash; |
1365 | ||
1366 | size = 1 << hash->size_bits; | |
1367 | for (i = 0; i < size; i++) { | |
b67bfe0d | 1368 | hlist_for_each_entry(entry, &hash->buckets[i], hlist) { |
33dc9b12 SR |
1369 | ret = add_hash_entry(new_hash, entry->ip); |
1370 | if (ret < 0) | |
1371 | goto free_hash; | |
1372 | } | |
1373 | } | |
1374 | ||
1375 | FTRACE_WARN_ON(new_hash->count != hash->count); | |
1376 | ||
1377 | return new_hash; | |
1378 | ||
1379 | free_hash: | |
1380 | free_ftrace_hash(new_hash); | |
1381 | return NULL; | |
1382 | } | |
1383 | ||
41fb61c2 | 1384 | static void |
84261912 | 1385 | ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1386 | static void |
84261912 | 1387 | ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); |
41fb61c2 | 1388 | |
f8b8be8a MH |
1389 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, |
1390 | struct ftrace_hash *new_hash); | |
1391 | ||
3e278c0d NK |
1392 | static struct ftrace_hash * |
1393 | __ftrace_hash_move(struct ftrace_hash *src) | |
33dc9b12 SR |
1394 | { |
1395 | struct ftrace_func_entry *entry; | |
b67bfe0d | 1396 | struct hlist_node *tn; |
33dc9b12 | 1397 | struct hlist_head *hhd; |
07fd5515 | 1398 | struct ftrace_hash *new_hash; |
33dc9b12 SR |
1399 | int size = src->count; |
1400 | int bits = 0; | |
1401 | int i; | |
1402 | ||
1403 | /* | |
3e278c0d | 1404 | * If the new source is empty, just return the empty_hash. |
33dc9b12 | 1405 | */ |
3e278c0d NK |
1406 | if (!src->count) |
1407 | return EMPTY_HASH; | |
33dc9b12 | 1408 | |
33dc9b12 SR |
1409 | /* |
1410 | * Make the hash size about 1/2 the # found | |
1411 | */ | |
1412 | for (size /= 2; size; size >>= 1) | |
1413 | bits++; | |
1414 | ||
1415 | /* Don't allocate too much */ | |
1416 | if (bits > FTRACE_HASH_MAX_BITS) | |
1417 | bits = FTRACE_HASH_MAX_BITS; | |
1418 | ||
07fd5515 SR |
1419 | new_hash = alloc_ftrace_hash(bits); |
1420 | if (!new_hash) | |
3e278c0d | 1421 | return NULL; |
33dc9b12 SR |
1422 | |
1423 | size = 1 << src->size_bits; | |
1424 | for (i = 0; i < size; i++) { | |
1425 | hhd = &src->buckets[i]; | |
b67bfe0d | 1426 | hlist_for_each_entry_safe(entry, tn, hhd, hlist) { |
33dc9b12 | 1427 | remove_hash_entry(src, entry); |
07fd5515 | 1428 | __add_hash_entry(new_hash, entry); |
33dc9b12 SR |
1429 | } |
1430 | } | |
1431 | ||
3e278c0d NK |
1432 | return new_hash; |
1433 | } | |
1434 | ||
1435 | static int | |
1436 | ftrace_hash_move(struct ftrace_ops *ops, int enable, | |
1437 | struct ftrace_hash **dst, struct ftrace_hash *src) | |
1438 | { | |
1439 | struct ftrace_hash *new_hash; | |
1440 | int ret; | |
1441 | ||
1442 | /* Reject setting notrace hash on IPMODIFY ftrace_ops */ | |
1443 | if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable) | |
1444 | return -EINVAL; | |
1445 | ||
1446 | new_hash = __ftrace_hash_move(src); | |
1447 | if (!new_hash) | |
1448 | return -ENOMEM; | |
1449 | ||
f8b8be8a MH |
1450 | /* Make sure this can be applied if it is IPMODIFY ftrace_ops */ |
1451 | if (enable) { | |
1452 | /* IPMODIFY should be updated only when filter_hash updating */ | |
1453 | ret = ftrace_hash_ipmodify_update(ops, new_hash); | |
1454 | if (ret < 0) { | |
1455 | free_ftrace_hash(new_hash); | |
1456 | return ret; | |
1457 | } | |
1458 | } | |
1459 | ||
5c27c775 MH |
1460 | /* |
1461 | * Remove the current set, update the hash and add | |
1462 | * them back. | |
1463 | */ | |
84261912 | 1464 | ftrace_hash_rec_disable_modify(ops, enable); |
5c27c775 | 1465 | |
07fd5515 | 1466 | rcu_assign_pointer(*dst, new_hash); |
07fd5515 | 1467 | |
84261912 | 1468 | ftrace_hash_rec_enable_modify(ops, enable); |
41fb61c2 | 1469 | |
5c27c775 | 1470 | return 0; |
33dc9b12 SR |
1471 | } |
1472 | ||
fef5aeee SRRH |
1473 | static bool hash_contains_ip(unsigned long ip, |
1474 | struct ftrace_ops_hash *hash) | |
1475 | { | |
1476 | /* | |
1477 | * The function record is a match if it exists in the filter | |
1478 | * hash and not in the notrace hash. Note, an emty hash is | |
1479 | * considered a match for the filter hash, but an empty | |
1480 | * notrace hash is considered not in the notrace hash. | |
1481 | */ | |
1482 | return (ftrace_hash_empty(hash->filter_hash) || | |
2b2c279c | 1483 | __ftrace_lookup_ip(hash->filter_hash, ip)) && |
fef5aeee | 1484 | (ftrace_hash_empty(hash->notrace_hash) || |
2b2c279c | 1485 | !__ftrace_lookup_ip(hash->notrace_hash, ip)); |
fef5aeee SRRH |
1486 | } |
1487 | ||
b848914c SR |
1488 | /* |
1489 | * Test the hashes for this ops to see if we want to call | |
1490 | * the ops->func or not. | |
1491 | * | |
1492 | * It's a match if the ip is in the ops->filter_hash or | |
1493 | * the filter_hash does not exist or is empty, | |
1494 | * AND | |
1495 | * the ip is not in the ops->notrace_hash. | |
cdbe61bf SR |
1496 | * |
1497 | * This needs to be called with preemption disabled as | |
1498 | * the hashes are freed with call_rcu_sched(). | |
b848914c SR |
1499 | */ |
1500 | static int | |
195a8afc | 1501 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c | 1502 | { |
fef5aeee | 1503 | struct ftrace_ops_hash hash; |
b848914c SR |
1504 | int ret; |
1505 | ||
195a8afc SRRH |
1506 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
1507 | /* | |
1508 | * There's a small race when adding ops that the ftrace handler | |
1509 | * that wants regs, may be called without them. We can not | |
1510 | * allow that handler to be called if regs is NULL. | |
1511 | */ | |
1512 | if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS)) | |
1513 | return 0; | |
1514 | #endif | |
1515 | ||
fef5aeee SRRH |
1516 | hash.filter_hash = rcu_dereference_raw_notrace(ops->func_hash->filter_hash); |
1517 | hash.notrace_hash = rcu_dereference_raw_notrace(ops->func_hash->notrace_hash); | |
b848914c | 1518 | |
fef5aeee | 1519 | if (hash_contains_ip(ip, &hash)) |
b848914c SR |
1520 | ret = 1; |
1521 | else | |
1522 | ret = 0; | |
b848914c SR |
1523 | |
1524 | return ret; | |
1525 | } | |
1526 | ||
493762fc SR |
1527 | /* |
1528 | * This is a double for. Do not use 'break' to break out of the loop, | |
1529 | * you must use a goto. | |
1530 | */ | |
1531 | #define do_for_each_ftrace_rec(pg, rec) \ | |
1532 | for (pg = ftrace_pages_start; pg; pg = pg->next) { \ | |
1533 | int _____i; \ | |
1534 | for (_____i = 0; _____i < pg->index; _____i++) { \ | |
1535 | rec = &pg->records[_____i]; | |
1536 | ||
1537 | #define while_for_each_ftrace_rec() \ | |
1538 | } \ | |
1539 | } | |
1540 | ||
5855fead SR |
1541 | |
1542 | static int ftrace_cmp_recs(const void *a, const void *b) | |
1543 | { | |
a650e02a SR |
1544 | const struct dyn_ftrace *key = a; |
1545 | const struct dyn_ftrace *rec = b; | |
5855fead | 1546 | |
a650e02a | 1547 | if (key->flags < rec->ip) |
5855fead | 1548 | return -1; |
a650e02a SR |
1549 | if (key->ip >= rec->ip + MCOUNT_INSN_SIZE) |
1550 | return 1; | |
5855fead SR |
1551 | return 0; |
1552 | } | |
1553 | ||
04cf31a7 ME |
1554 | /** |
1555 | * ftrace_location_range - return the first address of a traced location | |
1556 | * if it touches the given ip range | |
1557 | * @start: start of range to search. | |
1558 | * @end: end of range to search (inclusive). @end points to the last byte | |
1559 | * to check. | |
1560 | * | |
1561 | * Returns rec->ip if the related ftrace location is a least partly within | |
1562 | * the given address range. That is, the first address of the instruction | |
1563 | * that is either a NOP or call to the function tracer. It checks the ftrace | |
1564 | * internal tables to determine if the address belongs or not. | |
1565 | */ | |
1566 | unsigned long ftrace_location_range(unsigned long start, unsigned long end) | |
c88fd863 SR |
1567 | { |
1568 | struct ftrace_page *pg; | |
1569 | struct dyn_ftrace *rec; | |
5855fead | 1570 | struct dyn_ftrace key; |
c88fd863 | 1571 | |
a650e02a SR |
1572 | key.ip = start; |
1573 | key.flags = end; /* overload flags, as it is unsigned long */ | |
5855fead SR |
1574 | |
1575 | for (pg = ftrace_pages_start; pg; pg = pg->next) { | |
a650e02a SR |
1576 | if (end < pg->records[0].ip || |
1577 | start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) | |
9644302e | 1578 | continue; |
5855fead SR |
1579 | rec = bsearch(&key, pg->records, pg->index, |
1580 | sizeof(struct dyn_ftrace), | |
1581 | ftrace_cmp_recs); | |
1582 | if (rec) | |
f0cf973a | 1583 | return rec->ip; |
5855fead | 1584 | } |
c88fd863 SR |
1585 | |
1586 | return 0; | |
1587 | } | |
1588 | ||
a650e02a SR |
1589 | /** |
1590 | * ftrace_location - return true if the ip giving is a traced location | |
1591 | * @ip: the instruction pointer to check | |
1592 | * | |
f0cf973a | 1593 | * Returns rec->ip if @ip given is a pointer to a ftrace location. |
a650e02a SR |
1594 | * That is, the instruction that is either a NOP or call to |
1595 | * the function tracer. It checks the ftrace internal tables to | |
1596 | * determine if the address belongs or not. | |
1597 | */ | |
f0cf973a | 1598 | unsigned long ftrace_location(unsigned long ip) |
a650e02a SR |
1599 | { |
1600 | return ftrace_location_range(ip, ip); | |
1601 | } | |
1602 | ||
1603 | /** | |
1604 | * ftrace_text_reserved - return true if range contains an ftrace location | |
1605 | * @start: start of range to search | |
1606 | * @end: end of range to search (inclusive). @end points to the last byte to check. | |
1607 | * | |
1608 | * Returns 1 if @start and @end contains a ftrace location. | |
1609 | * That is, the instruction that is either a NOP or call to | |
1610 | * the function tracer. It checks the ftrace internal tables to | |
1611 | * determine if the address belongs or not. | |
1612 | */ | |
d88471cb | 1613 | int ftrace_text_reserved(const void *start, const void *end) |
a650e02a | 1614 | { |
f0cf973a SR |
1615 | unsigned long ret; |
1616 | ||
1617 | ret = ftrace_location_range((unsigned long)start, | |
1618 | (unsigned long)end); | |
1619 | ||
1620 | return (int)!!ret; | |
a650e02a SR |
1621 | } |
1622 | ||
4fbb48cb SRRH |
1623 | /* Test if ops registered to this rec needs regs */ |
1624 | static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec) | |
1625 | { | |
1626 | struct ftrace_ops *ops; | |
1627 | bool keep_regs = false; | |
1628 | ||
1629 | for (ops = ftrace_ops_list; | |
1630 | ops != &ftrace_list_end; ops = ops->next) { | |
1631 | /* pass rec in as regs to have non-NULL val */ | |
1632 | if (ftrace_ops_test(ops, rec->ip, rec)) { | |
1633 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1634 | keep_regs = true; | |
1635 | break; | |
1636 | } | |
1637 | } | |
1638 | } | |
1639 | ||
1640 | return keep_regs; | |
1641 | } | |
1642 | ||
84b6d3e6 | 1643 | static bool __ftrace_hash_rec_update(struct ftrace_ops *ops, |
ed926f9b SR |
1644 | int filter_hash, |
1645 | bool inc) | |
1646 | { | |
1647 | struct ftrace_hash *hash; | |
1648 | struct ftrace_hash *other_hash; | |
1649 | struct ftrace_page *pg; | |
1650 | struct dyn_ftrace *rec; | |
84b6d3e6 | 1651 | bool update = false; |
ed926f9b SR |
1652 | int count = 0; |
1653 | int all = 0; | |
1654 | ||
1655 | /* Only update if the ops has been registered */ | |
1656 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
84b6d3e6 | 1657 | return false; |
ed926f9b SR |
1658 | |
1659 | /* | |
1660 | * In the filter_hash case: | |
1661 | * If the count is zero, we update all records. | |
1662 | * Otherwise we just update the items in the hash. | |
1663 | * | |
1664 | * In the notrace_hash case: | |
1665 | * We enable the update in the hash. | |
1666 | * As disabling notrace means enabling the tracing, | |
1667 | * and enabling notrace means disabling, the inc variable | |
1668 | * gets inversed. | |
1669 | */ | |
1670 | if (filter_hash) { | |
33b7f99c SRRH |
1671 | hash = ops->func_hash->filter_hash; |
1672 | other_hash = ops->func_hash->notrace_hash; | |
06a51d93 | 1673 | if (ftrace_hash_empty(hash)) |
ed926f9b SR |
1674 | all = 1; |
1675 | } else { | |
1676 | inc = !inc; | |
33b7f99c SRRH |
1677 | hash = ops->func_hash->notrace_hash; |
1678 | other_hash = ops->func_hash->filter_hash; | |
ed926f9b SR |
1679 | /* |
1680 | * If the notrace hash has no items, | |
1681 | * then there's nothing to do. | |
1682 | */ | |
06a51d93 | 1683 | if (ftrace_hash_empty(hash)) |
84b6d3e6 | 1684 | return false; |
ed926f9b SR |
1685 | } |
1686 | ||
1687 | do_for_each_ftrace_rec(pg, rec) { | |
1688 | int in_other_hash = 0; | |
1689 | int in_hash = 0; | |
1690 | int match = 0; | |
1691 | ||
b7ffffbb SRRH |
1692 | if (rec->flags & FTRACE_FL_DISABLED) |
1693 | continue; | |
1694 | ||
ed926f9b SR |
1695 | if (all) { |
1696 | /* | |
1697 | * Only the filter_hash affects all records. | |
1698 | * Update if the record is not in the notrace hash. | |
1699 | */ | |
b848914c | 1700 | if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip)) |
ed926f9b SR |
1701 | match = 1; |
1702 | } else { | |
06a51d93 SR |
1703 | in_hash = !!ftrace_lookup_ip(hash, rec->ip); |
1704 | in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip); | |
ed926f9b SR |
1705 | |
1706 | /* | |
19eab4a4 SRRH |
1707 | * If filter_hash is set, we want to match all functions |
1708 | * that are in the hash but not in the other hash. | |
ed926f9b | 1709 | * |
19eab4a4 SRRH |
1710 | * If filter_hash is not set, then we are decrementing. |
1711 | * That means we match anything that is in the hash | |
1712 | * and also in the other_hash. That is, we need to turn | |
1713 | * off functions in the other hash because they are disabled | |
1714 | * by this hash. | |
ed926f9b SR |
1715 | */ |
1716 | if (filter_hash && in_hash && !in_other_hash) | |
1717 | match = 1; | |
1718 | else if (!filter_hash && in_hash && | |
06a51d93 | 1719 | (in_other_hash || ftrace_hash_empty(other_hash))) |
ed926f9b SR |
1720 | match = 1; |
1721 | } | |
1722 | if (!match) | |
1723 | continue; | |
1724 | ||
1725 | if (inc) { | |
1726 | rec->flags++; | |
0376bde1 | 1727 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX)) |
84b6d3e6 | 1728 | return false; |
79922b80 SRRH |
1729 | |
1730 | /* | |
1731 | * If there's only a single callback registered to a | |
1732 | * function, and the ops has a trampoline registered | |
1733 | * for it, then we can call it directly. | |
1734 | */ | |
fef5aeee | 1735 | if (ftrace_rec_count(rec) == 1 && ops->trampoline) |
79922b80 | 1736 | rec->flags |= FTRACE_FL_TRAMP; |
fef5aeee | 1737 | else |
79922b80 SRRH |
1738 | /* |
1739 | * If we are adding another function callback | |
1740 | * to this function, and the previous had a | |
bce0b6c5 SRRH |
1741 | * custom trampoline in use, then we need to go |
1742 | * back to the default trampoline. | |
79922b80 | 1743 | */ |
fef5aeee | 1744 | rec->flags &= ~FTRACE_FL_TRAMP; |
79922b80 | 1745 | |
08f6fba5 SR |
1746 | /* |
1747 | * If any ops wants regs saved for this function | |
1748 | * then all ops will get saved regs. | |
1749 | */ | |
1750 | if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) | |
1751 | rec->flags |= FTRACE_FL_REGS; | |
ed926f9b | 1752 | } else { |
0376bde1 | 1753 | if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0)) |
84b6d3e6 | 1754 | return false; |
ed926f9b | 1755 | rec->flags--; |
79922b80 | 1756 | |
4fbb48cb SRRH |
1757 | /* |
1758 | * If the rec had REGS enabled and the ops that is | |
1759 | * being removed had REGS set, then see if there is | |
1760 | * still any ops for this record that wants regs. | |
1761 | * If not, we can stop recording them. | |
1762 | */ | |
0376bde1 | 1763 | if (ftrace_rec_count(rec) > 0 && |
4fbb48cb SRRH |
1764 | rec->flags & FTRACE_FL_REGS && |
1765 | ops->flags & FTRACE_OPS_FL_SAVE_REGS) { | |
1766 | if (!test_rec_ops_needs_regs(rec)) | |
1767 | rec->flags &= ~FTRACE_FL_REGS; | |
1768 | } | |
79922b80 | 1769 | |
fef5aeee SRRH |
1770 | /* |
1771 | * If the rec had TRAMP enabled, then it needs to | |
1772 | * be cleared. As TRAMP can only be enabled iff | |
1773 | * there is only a single ops attached to it. | |
1774 | * In otherwords, always disable it on decrementing. | |
1775 | * In the future, we may set it if rec count is | |
1776 | * decremented to one, and the ops that is left | |
1777 | * has a trampoline. | |
1778 | */ | |
1779 | rec->flags &= ~FTRACE_FL_TRAMP; | |
1780 | ||
79922b80 SRRH |
1781 | /* |
1782 | * flags will be cleared in ftrace_check_record() | |
1783 | * if rec count is zero. | |
1784 | */ | |
ed926f9b SR |
1785 | } |
1786 | count++; | |
84b6d3e6 JO |
1787 | |
1788 | /* Must match FTRACE_UPDATE_CALLS in ftrace_modify_all_code() */ | |
1789 | update |= ftrace_test_record(rec, 1) != FTRACE_UPDATE_IGNORE; | |
1790 | ||
ed926f9b SR |
1791 | /* Shortcut, if we handled all records, we are done. */ |
1792 | if (!all && count == hash->count) | |
84b6d3e6 | 1793 | return update; |
ed926f9b | 1794 | } while_for_each_ftrace_rec(); |
84b6d3e6 JO |
1795 | |
1796 | return update; | |
ed926f9b SR |
1797 | } |
1798 | ||
84b6d3e6 | 1799 | static bool ftrace_hash_rec_disable(struct ftrace_ops *ops, |
ed926f9b SR |
1800 | int filter_hash) |
1801 | { | |
84b6d3e6 | 1802 | return __ftrace_hash_rec_update(ops, filter_hash, 0); |
ed926f9b SR |
1803 | } |
1804 | ||
84b6d3e6 | 1805 | static bool ftrace_hash_rec_enable(struct ftrace_ops *ops, |
ed926f9b SR |
1806 | int filter_hash) |
1807 | { | |
84b6d3e6 | 1808 | return __ftrace_hash_rec_update(ops, filter_hash, 1); |
ed926f9b SR |
1809 | } |
1810 | ||
84261912 SRRH |
1811 | static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops, |
1812 | int filter_hash, int inc) | |
1813 | { | |
1814 | struct ftrace_ops *op; | |
1815 | ||
1816 | __ftrace_hash_rec_update(ops, filter_hash, inc); | |
1817 | ||
1818 | if (ops->func_hash != &global_ops.local_hash) | |
1819 | return; | |
1820 | ||
1821 | /* | |
1822 | * If the ops shares the global_ops hash, then we need to update | |
1823 | * all ops that are enabled and use this hash. | |
1824 | */ | |
1825 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
1826 | /* Already done */ | |
1827 | if (op == ops) | |
1828 | continue; | |
1829 | if (op->func_hash == &global_ops.local_hash) | |
1830 | __ftrace_hash_rec_update(op, filter_hash, inc); | |
1831 | } while_for_each_ftrace_op(op); | |
1832 | } | |
1833 | ||
1834 | static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, | |
1835 | int filter_hash) | |
1836 | { | |
1837 | ftrace_hash_rec_update_modify(ops, filter_hash, 0); | |
1838 | } | |
1839 | ||
1840 | static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, | |
1841 | int filter_hash) | |
1842 | { | |
1843 | ftrace_hash_rec_update_modify(ops, filter_hash, 1); | |
1844 | } | |
1845 | ||
f8b8be8a MH |
1846 | /* |
1847 | * Try to update IPMODIFY flag on each ftrace_rec. Return 0 if it is OK | |
1848 | * or no-needed to update, -EBUSY if it detects a conflict of the flag | |
1849 | * on a ftrace_rec, and -EINVAL if the new_hash tries to trace all recs. | |
1850 | * Note that old_hash and new_hash has below meanings | |
1851 | * - If the hash is NULL, it hits all recs (if IPMODIFY is set, this is rejected) | |
1852 | * - If the hash is EMPTY_HASH, it hits nothing | |
1853 | * - Anything else hits the recs which match the hash entries. | |
1854 | */ | |
1855 | static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops, | |
1856 | struct ftrace_hash *old_hash, | |
1857 | struct ftrace_hash *new_hash) | |
1858 | { | |
1859 | struct ftrace_page *pg; | |
1860 | struct dyn_ftrace *rec, *end = NULL; | |
1861 | int in_old, in_new; | |
1862 | ||
1863 | /* Only update if the ops has been registered */ | |
1864 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
1865 | return 0; | |
1866 | ||
1867 | if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY)) | |
1868 | return 0; | |
1869 | ||
1870 | /* | |
1871 | * Since the IPMODIFY is a very address sensitive action, we do not | |
1872 | * allow ftrace_ops to set all functions to new hash. | |
1873 | */ | |
1874 | if (!new_hash || !old_hash) | |
1875 | return -EINVAL; | |
1876 | ||
1877 | /* Update rec->flags */ | |
1878 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1879 | |
1880 | if (rec->flags & FTRACE_FL_DISABLED) | |
1881 | continue; | |
1882 | ||
f8b8be8a MH |
1883 | /* We need to update only differences of filter_hash */ |
1884 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1885 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1886 | if (in_old == in_new) | |
1887 | continue; | |
1888 | ||
1889 | if (in_new) { | |
1890 | /* New entries must ensure no others are using it */ | |
1891 | if (rec->flags & FTRACE_FL_IPMODIFY) | |
1892 | goto rollback; | |
1893 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1894 | } else /* Removed entry */ | |
1895 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1896 | } while_for_each_ftrace_rec(); | |
1897 | ||
1898 | return 0; | |
1899 | ||
1900 | rollback: | |
1901 | end = rec; | |
1902 | ||
1903 | /* Roll back what we did above */ | |
1904 | do_for_each_ftrace_rec(pg, rec) { | |
546fece4 SRRH |
1905 | |
1906 | if (rec->flags & FTRACE_FL_DISABLED) | |
1907 | continue; | |
1908 | ||
f8b8be8a MH |
1909 | if (rec == end) |
1910 | goto err_out; | |
1911 | ||
1912 | in_old = !!ftrace_lookup_ip(old_hash, rec->ip); | |
1913 | in_new = !!ftrace_lookup_ip(new_hash, rec->ip); | |
1914 | if (in_old == in_new) | |
1915 | continue; | |
1916 | ||
1917 | if (in_new) | |
1918 | rec->flags &= ~FTRACE_FL_IPMODIFY; | |
1919 | else | |
1920 | rec->flags |= FTRACE_FL_IPMODIFY; | |
1921 | } while_for_each_ftrace_rec(); | |
1922 | ||
1923 | err_out: | |
1924 | return -EBUSY; | |
1925 | } | |
1926 | ||
1927 | static int ftrace_hash_ipmodify_enable(struct ftrace_ops *ops) | |
1928 | { | |
1929 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1930 | ||
1931 | if (ftrace_hash_empty(hash)) | |
1932 | hash = NULL; | |
1933 | ||
1934 | return __ftrace_hash_update_ipmodify(ops, EMPTY_HASH, hash); | |
1935 | } | |
1936 | ||
1937 | /* Disabling always succeeds */ | |
1938 | static void ftrace_hash_ipmodify_disable(struct ftrace_ops *ops) | |
1939 | { | |
1940 | struct ftrace_hash *hash = ops->func_hash->filter_hash; | |
1941 | ||
1942 | if (ftrace_hash_empty(hash)) | |
1943 | hash = NULL; | |
1944 | ||
1945 | __ftrace_hash_update_ipmodify(ops, hash, EMPTY_HASH); | |
1946 | } | |
1947 | ||
1948 | static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops, | |
1949 | struct ftrace_hash *new_hash) | |
1950 | { | |
1951 | struct ftrace_hash *old_hash = ops->func_hash->filter_hash; | |
1952 | ||
1953 | if (ftrace_hash_empty(old_hash)) | |
1954 | old_hash = NULL; | |
1955 | ||
1956 | if (ftrace_hash_empty(new_hash)) | |
1957 | new_hash = NULL; | |
1958 | ||
1959 | return __ftrace_hash_update_ipmodify(ops, old_hash, new_hash); | |
1960 | } | |
1961 | ||
b05086c7 | 1962 | static void print_ip_ins(const char *fmt, const unsigned char *p) |
b17e8a37 SR |
1963 | { |
1964 | int i; | |
1965 | ||
1966 | printk(KERN_CONT "%s", fmt); | |
1967 | ||
1968 | for (i = 0; i < MCOUNT_INSN_SIZE; i++) | |
1969 | printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]); | |
1970 | } | |
1971 | ||
4fd3279b SRRH |
1972 | static struct ftrace_ops * |
1973 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec); | |
39daa7b9 SRRH |
1974 | static struct ftrace_ops * |
1975 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops); | |
4fd3279b | 1976 | |
02a392a0 | 1977 | enum ftrace_bug_type ftrace_bug_type; |
b05086c7 | 1978 | const void *ftrace_expected; |
02a392a0 SRRH |
1979 | |
1980 | static void print_bug_type(void) | |
1981 | { | |
1982 | switch (ftrace_bug_type) { | |
1983 | case FTRACE_BUG_UNKNOWN: | |
1984 | break; | |
1985 | case FTRACE_BUG_INIT: | |
1986 | pr_info("Initializing ftrace call sites\n"); | |
1987 | break; | |
1988 | case FTRACE_BUG_NOP: | |
1989 | pr_info("Setting ftrace call site to NOP\n"); | |
1990 | break; | |
1991 | case FTRACE_BUG_CALL: | |
1992 | pr_info("Setting ftrace call site to call ftrace function\n"); | |
1993 | break; | |
1994 | case FTRACE_BUG_UPDATE: | |
1995 | pr_info("Updating ftrace call site to call a different ftrace function\n"); | |
1996 | break; | |
1997 | } | |
1998 | } | |
1999 | ||
c88fd863 SR |
2000 | /** |
2001 | * ftrace_bug - report and shutdown function tracer | |
2002 | * @failed: The failed type (EFAULT, EINVAL, EPERM) | |
4fd3279b | 2003 | * @rec: The record that failed |
c88fd863 SR |
2004 | * |
2005 | * The arch code that enables or disables the function tracing | |
2006 | * can call ftrace_bug() when it has detected a problem in | |
2007 | * modifying the code. @failed should be one of either: | |
2008 | * EFAULT - if the problem happens on reading the @ip address | |
2009 | * EINVAL - if what is read at @ip is not what was expected | |
2010 | * EPERM - if the problem happens on writting to the @ip address | |
2011 | */ | |
4fd3279b | 2012 | void ftrace_bug(int failed, struct dyn_ftrace *rec) |
b17e8a37 | 2013 | { |
4fd3279b SRRH |
2014 | unsigned long ip = rec ? rec->ip : 0; |
2015 | ||
b17e8a37 SR |
2016 | switch (failed) { |
2017 | case -EFAULT: | |
2018 | FTRACE_WARN_ON_ONCE(1); | |
2019 | pr_info("ftrace faulted on modifying "); | |
2020 | print_ip_sym(ip); | |
2021 | break; | |
2022 | case -EINVAL: | |
2023 | FTRACE_WARN_ON_ONCE(1); | |
2024 | pr_info("ftrace failed to modify "); | |
2025 | print_ip_sym(ip); | |
b05086c7 | 2026 | print_ip_ins(" actual: ", (unsigned char *)ip); |
4fd3279b | 2027 | pr_cont("\n"); |
b05086c7 SRRH |
2028 | if (ftrace_expected) { |
2029 | print_ip_ins(" expected: ", ftrace_expected); | |
2030 | pr_cont("\n"); | |
2031 | } | |
b17e8a37 SR |
2032 | break; |
2033 | case -EPERM: | |
2034 | FTRACE_WARN_ON_ONCE(1); | |
2035 | pr_info("ftrace faulted on writing "); | |
2036 | print_ip_sym(ip); | |
2037 | break; | |
2038 | default: | |
2039 | FTRACE_WARN_ON_ONCE(1); | |
2040 | pr_info("ftrace faulted on unknown error "); | |
2041 | print_ip_sym(ip); | |
2042 | } | |
02a392a0 | 2043 | print_bug_type(); |
4fd3279b SRRH |
2044 | if (rec) { |
2045 | struct ftrace_ops *ops = NULL; | |
2046 | ||
2047 | pr_info("ftrace record flags: %lx\n", rec->flags); | |
2048 | pr_cont(" (%ld)%s", ftrace_rec_count(rec), | |
2049 | rec->flags & FTRACE_FL_REGS ? " R" : " "); | |
2050 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2051 | ops = ftrace_find_tramp_ops_any(rec); | |
39daa7b9 SRRH |
2052 | if (ops) { |
2053 | do { | |
2054 | pr_cont("\ttramp: %pS (%pS)", | |
2055 | (void *)ops->trampoline, | |
2056 | (void *)ops->func); | |
2057 | ops = ftrace_find_tramp_ops_next(rec, ops); | |
2058 | } while (ops); | |
2059 | } else | |
4fd3279b SRRH |
2060 | pr_cont("\ttramp: ERROR!"); |
2061 | ||
2062 | } | |
2063 | ip = ftrace_get_addr_curr(rec); | |
39daa7b9 | 2064 | pr_cont("\n expected tramp: %lx\n", ip); |
4fd3279b | 2065 | } |
b17e8a37 SR |
2066 | } |
2067 | ||
c88fd863 | 2068 | static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) |
5072c59f | 2069 | { |
64fbcd16 | 2070 | unsigned long flag = 0UL; |
e7d3737e | 2071 | |
02a392a0 SRRH |
2072 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2073 | ||
b7ffffbb SRRH |
2074 | if (rec->flags & FTRACE_FL_DISABLED) |
2075 | return FTRACE_UPDATE_IGNORE; | |
2076 | ||
982c350b | 2077 | /* |
30fb6aa7 | 2078 | * If we are updating calls: |
982c350b | 2079 | * |
ed926f9b SR |
2080 | * If the record has a ref count, then we need to enable it |
2081 | * because someone is using it. | |
982c350b | 2082 | * |
ed926f9b SR |
2083 | * Otherwise we make sure its disabled. |
2084 | * | |
30fb6aa7 | 2085 | * If we are disabling calls, then disable all records that |
ed926f9b | 2086 | * are enabled. |
982c350b | 2087 | */ |
0376bde1 | 2088 | if (enable && ftrace_rec_count(rec)) |
ed926f9b | 2089 | flag = FTRACE_FL_ENABLED; |
982c350b | 2090 | |
08f6fba5 | 2091 | /* |
79922b80 SRRH |
2092 | * If enabling and the REGS flag does not match the REGS_EN, or |
2093 | * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore | |
2094 | * this record. Set flags to fail the compare against ENABLED. | |
08f6fba5 | 2095 | */ |
79922b80 SRRH |
2096 | if (flag) { |
2097 | if (!(rec->flags & FTRACE_FL_REGS) != | |
2098 | !(rec->flags & FTRACE_FL_REGS_EN)) | |
2099 | flag |= FTRACE_FL_REGS; | |
2100 | ||
2101 | if (!(rec->flags & FTRACE_FL_TRAMP) != | |
2102 | !(rec->flags & FTRACE_FL_TRAMP_EN)) | |
2103 | flag |= FTRACE_FL_TRAMP; | |
2104 | } | |
08f6fba5 | 2105 | |
64fbcd16 XG |
2106 | /* If the state of this record hasn't changed, then do nothing */ |
2107 | if ((rec->flags & FTRACE_FL_ENABLED) == flag) | |
c88fd863 | 2108 | return FTRACE_UPDATE_IGNORE; |
982c350b | 2109 | |
64fbcd16 | 2110 | if (flag) { |
08f6fba5 SR |
2111 | /* Save off if rec is being enabled (for return value) */ |
2112 | flag ^= rec->flags & FTRACE_FL_ENABLED; | |
2113 | ||
2114 | if (update) { | |
c88fd863 | 2115 | rec->flags |= FTRACE_FL_ENABLED; |
08f6fba5 SR |
2116 | if (flag & FTRACE_FL_REGS) { |
2117 | if (rec->flags & FTRACE_FL_REGS) | |
2118 | rec->flags |= FTRACE_FL_REGS_EN; | |
2119 | else | |
2120 | rec->flags &= ~FTRACE_FL_REGS_EN; | |
2121 | } | |
79922b80 SRRH |
2122 | if (flag & FTRACE_FL_TRAMP) { |
2123 | if (rec->flags & FTRACE_FL_TRAMP) | |
2124 | rec->flags |= FTRACE_FL_TRAMP_EN; | |
2125 | else | |
2126 | rec->flags &= ~FTRACE_FL_TRAMP_EN; | |
2127 | } | |
08f6fba5 SR |
2128 | } |
2129 | ||
2130 | /* | |
2131 | * If this record is being updated from a nop, then | |
2132 | * return UPDATE_MAKE_CALL. | |
08f6fba5 SR |
2133 | * Otherwise, |
2134 | * return UPDATE_MODIFY_CALL to tell the caller to convert | |
f1b2f2bd | 2135 | * from the save regs, to a non-save regs function or |
79922b80 | 2136 | * vice versa, or from a trampoline call. |
08f6fba5 | 2137 | */ |
02a392a0 SRRH |
2138 | if (flag & FTRACE_FL_ENABLED) { |
2139 | ftrace_bug_type = FTRACE_BUG_CALL; | |
08f6fba5 | 2140 | return FTRACE_UPDATE_MAKE_CALL; |
02a392a0 | 2141 | } |
f1b2f2bd | 2142 | |
02a392a0 | 2143 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
f1b2f2bd | 2144 | return FTRACE_UPDATE_MODIFY_CALL; |
c88fd863 SR |
2145 | } |
2146 | ||
08f6fba5 SR |
2147 | if (update) { |
2148 | /* If there's no more users, clear all flags */ | |
0376bde1 | 2149 | if (!ftrace_rec_count(rec)) |
08f6fba5 SR |
2150 | rec->flags = 0; |
2151 | else | |
b24d443b SRRH |
2152 | /* |
2153 | * Just disable the record, but keep the ops TRAMP | |
2154 | * and REGS states. The _EN flags must be disabled though. | |
2155 | */ | |
2156 | rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN | | |
2157 | FTRACE_FL_REGS_EN); | |
08f6fba5 | 2158 | } |
c88fd863 | 2159 | |
02a392a0 | 2160 | ftrace_bug_type = FTRACE_BUG_NOP; |
c88fd863 SR |
2161 | return FTRACE_UPDATE_MAKE_NOP; |
2162 | } | |
2163 | ||
2164 | /** | |
2165 | * ftrace_update_record, set a record that now is tracing or not | |
2166 | * @rec: the record to update | |
2167 | * @enable: set to 1 if the record is tracing, zero to force disable | |
2168 | * | |
2169 | * The records that represent all functions that can be traced need | |
2170 | * to be updated when tracing has been enabled. | |
2171 | */ | |
2172 | int ftrace_update_record(struct dyn_ftrace *rec, int enable) | |
2173 | { | |
2174 | return ftrace_check_record(rec, enable, 1); | |
2175 | } | |
2176 | ||
2177 | /** | |
2178 | * ftrace_test_record, check if the record has been enabled or not | |
2179 | * @rec: the record to test | |
2180 | * @enable: set to 1 to check if enabled, 0 if it is disabled | |
2181 | * | |
2182 | * The arch code may need to test if a record is already set to | |
2183 | * tracing to determine how to modify the function code that it | |
2184 | * represents. | |
2185 | */ | |
2186 | int ftrace_test_record(struct dyn_ftrace *rec, int enable) | |
2187 | { | |
2188 | return ftrace_check_record(rec, enable, 0); | |
2189 | } | |
2190 | ||
5fecaa04 SRRH |
2191 | static struct ftrace_ops * |
2192 | ftrace_find_tramp_ops_any(struct dyn_ftrace *rec) | |
2193 | { | |
2194 | struct ftrace_ops *op; | |
fef5aeee | 2195 | unsigned long ip = rec->ip; |
5fecaa04 SRRH |
2196 | |
2197 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2198 | ||
2199 | if (!op->trampoline) | |
2200 | continue; | |
2201 | ||
fef5aeee | 2202 | if (hash_contains_ip(ip, op->func_hash)) |
5fecaa04 SRRH |
2203 | return op; |
2204 | } while_for_each_ftrace_op(op); | |
2205 | ||
2206 | return NULL; | |
2207 | } | |
2208 | ||
39daa7b9 SRRH |
2209 | static struct ftrace_ops * |
2210 | ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, | |
2211 | struct ftrace_ops *op) | |
2212 | { | |
2213 | unsigned long ip = rec->ip; | |
2214 | ||
2215 | while_for_each_ftrace_op(op) { | |
2216 | ||
2217 | if (!op->trampoline) | |
2218 | continue; | |
2219 | ||
2220 | if (hash_contains_ip(ip, op->func_hash)) | |
2221 | return op; | |
2222 | } | |
2223 | ||
2224 | return NULL; | |
2225 | } | |
2226 | ||
79922b80 SRRH |
2227 | static struct ftrace_ops * |
2228 | ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec) | |
2229 | { | |
2230 | struct ftrace_ops *op; | |
fef5aeee | 2231 | unsigned long ip = rec->ip; |
79922b80 | 2232 | |
fef5aeee SRRH |
2233 | /* |
2234 | * Need to check removed ops first. | |
2235 | * If they are being removed, and this rec has a tramp, | |
2236 | * and this rec is in the ops list, then it would be the | |
2237 | * one with the tramp. | |
2238 | */ | |
2239 | if (removed_ops) { | |
2240 | if (hash_contains_ip(ip, &removed_ops->old_hash)) | |
79922b80 SRRH |
2241 | return removed_ops; |
2242 | } | |
2243 | ||
fef5aeee SRRH |
2244 | /* |
2245 | * Need to find the current trampoline for a rec. | |
2246 | * Now, a trampoline is only attached to a rec if there | |
2247 | * was a single 'ops' attached to it. But this can be called | |
2248 | * when we are adding another op to the rec or removing the | |
2249 | * current one. Thus, if the op is being added, we can | |
2250 | * ignore it because it hasn't attached itself to the rec | |
4fc40904 SRRH |
2251 | * yet. |
2252 | * | |
2253 | * If an ops is being modified (hooking to different functions) | |
2254 | * then we don't care about the new functions that are being | |
2255 | * added, just the old ones (that are probably being removed). | |
2256 | * | |
2257 | * If we are adding an ops to a function that already is using | |
2258 | * a trampoline, it needs to be removed (trampolines are only | |
2259 | * for single ops connected), then an ops that is not being | |
2260 | * modified also needs to be checked. | |
fef5aeee | 2261 | */ |
79922b80 | 2262 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
fef5aeee SRRH |
2263 | |
2264 | if (!op->trampoline) | |
2265 | continue; | |
2266 | ||
2267 | /* | |
2268 | * If the ops is being added, it hasn't gotten to | |
2269 | * the point to be removed from this tree yet. | |
2270 | */ | |
2271 | if (op->flags & FTRACE_OPS_FL_ADDING) | |
79922b80 SRRH |
2272 | continue; |
2273 | ||
4fc40904 | 2274 | |
fef5aeee | 2275 | /* |
4fc40904 SRRH |
2276 | * If the ops is being modified and is in the old |
2277 | * hash, then it is probably being removed from this | |
2278 | * function. | |
fef5aeee | 2279 | */ |
fef5aeee SRRH |
2280 | if ((op->flags & FTRACE_OPS_FL_MODIFYING) && |
2281 | hash_contains_ip(ip, &op->old_hash)) | |
79922b80 | 2282 | return op; |
4fc40904 SRRH |
2283 | /* |
2284 | * If the ops is not being added or modified, and it's | |
2285 | * in its normal filter hash, then this must be the one | |
2286 | * we want! | |
2287 | */ | |
2288 | if (!(op->flags & FTRACE_OPS_FL_MODIFYING) && | |
2289 | hash_contains_ip(ip, op->func_hash)) | |
2290 | return op; | |
79922b80 SRRH |
2291 | |
2292 | } while_for_each_ftrace_op(op); | |
2293 | ||
2294 | return NULL; | |
2295 | } | |
2296 | ||
2297 | static struct ftrace_ops * | |
2298 | ftrace_find_tramp_ops_new(struct dyn_ftrace *rec) | |
2299 | { | |
2300 | struct ftrace_ops *op; | |
fef5aeee | 2301 | unsigned long ip = rec->ip; |
79922b80 SRRH |
2302 | |
2303 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
2304 | /* pass rec in as regs to have non-NULL val */ | |
fef5aeee | 2305 | if (hash_contains_ip(ip, op->func_hash)) |
79922b80 SRRH |
2306 | return op; |
2307 | } while_for_each_ftrace_op(op); | |
2308 | ||
2309 | return NULL; | |
2310 | } | |
2311 | ||
7413af1f SRRH |
2312 | /** |
2313 | * ftrace_get_addr_new - Get the call address to set to | |
2314 | * @rec: The ftrace record descriptor | |
2315 | * | |
2316 | * If the record has the FTRACE_FL_REGS set, that means that it | |
2317 | * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS | |
2318 | * is not not set, then it wants to convert to the normal callback. | |
2319 | * | |
2320 | * Returns the address of the trampoline to set to | |
2321 | */ | |
2322 | unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec) | |
2323 | { | |
79922b80 SRRH |
2324 | struct ftrace_ops *ops; |
2325 | ||
2326 | /* Trampolines take precedence over regs */ | |
2327 | if (rec->flags & FTRACE_FL_TRAMP) { | |
2328 | ops = ftrace_find_tramp_ops_new(rec); | |
2329 | if (FTRACE_WARN_ON(!ops || !ops->trampoline)) { | |
bce0b6c5 SRRH |
2330 | pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n", |
2331 | (void *)rec->ip, (void *)rec->ip, rec->flags); | |
79922b80 SRRH |
2332 | /* Ftrace is shutting down, return anything */ |
2333 | return (unsigned long)FTRACE_ADDR; | |
2334 | } | |
2335 | return ops->trampoline; | |
2336 | } | |
2337 | ||
7413af1f SRRH |
2338 | if (rec->flags & FTRACE_FL_REGS) |
2339 | return (unsigned long)FTRACE_REGS_ADDR; | |
2340 | else | |
2341 | return (unsigned long)FTRACE_ADDR; | |
2342 | } | |
2343 | ||
2344 | /** | |
2345 | * ftrace_get_addr_curr - Get the call address that is already there | |
2346 | * @rec: The ftrace record descriptor | |
2347 | * | |
2348 | * The FTRACE_FL_REGS_EN is set when the record already points to | |
2349 | * a function that saves all the regs. Basically the '_EN' version | |
2350 | * represents the current state of the function. | |
2351 | * | |
2352 | * Returns the address of the trampoline that is currently being called | |
2353 | */ | |
2354 | unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec) | |
2355 | { | |
79922b80 SRRH |
2356 | struct ftrace_ops *ops; |
2357 | ||
2358 | /* Trampolines take precedence over regs */ | |
2359 | if (rec->flags & FTRACE_FL_TRAMP_EN) { | |
2360 | ops = ftrace_find_tramp_ops_curr(rec); | |
2361 | if (FTRACE_WARN_ON(!ops)) { | |
a395d6a7 JP |
2362 | pr_warn("Bad trampoline accounting at: %p (%pS)\n", |
2363 | (void *)rec->ip, (void *)rec->ip); | |
79922b80 SRRH |
2364 | /* Ftrace is shutting down, return anything */ |
2365 | return (unsigned long)FTRACE_ADDR; | |
2366 | } | |
2367 | return ops->trampoline; | |
2368 | } | |
2369 | ||
7413af1f SRRH |
2370 | if (rec->flags & FTRACE_FL_REGS_EN) |
2371 | return (unsigned long)FTRACE_REGS_ADDR; | |
2372 | else | |
2373 | return (unsigned long)FTRACE_ADDR; | |
2374 | } | |
2375 | ||
c88fd863 SR |
2376 | static int |
2377 | __ftrace_replace_code(struct dyn_ftrace *rec, int enable) | |
2378 | { | |
08f6fba5 | 2379 | unsigned long ftrace_old_addr; |
c88fd863 SR |
2380 | unsigned long ftrace_addr; |
2381 | int ret; | |
2382 | ||
7c0868e0 | 2383 | ftrace_addr = ftrace_get_addr_new(rec); |
c88fd863 | 2384 | |
7c0868e0 SRRH |
2385 | /* This needs to be done before we call ftrace_update_record */ |
2386 | ftrace_old_addr = ftrace_get_addr_curr(rec); | |
2387 | ||
2388 | ret = ftrace_update_record(rec, enable); | |
08f6fba5 | 2389 | |
02a392a0 SRRH |
2390 | ftrace_bug_type = FTRACE_BUG_UNKNOWN; |
2391 | ||
c88fd863 SR |
2392 | switch (ret) { |
2393 | case FTRACE_UPDATE_IGNORE: | |
2394 | return 0; | |
2395 | ||
2396 | case FTRACE_UPDATE_MAKE_CALL: | |
02a392a0 | 2397 | ftrace_bug_type = FTRACE_BUG_CALL; |
64fbcd16 | 2398 | return ftrace_make_call(rec, ftrace_addr); |
c88fd863 SR |
2399 | |
2400 | case FTRACE_UPDATE_MAKE_NOP: | |
02a392a0 | 2401 | ftrace_bug_type = FTRACE_BUG_NOP; |
39b5552c | 2402 | return ftrace_make_nop(NULL, rec, ftrace_old_addr); |
08f6fba5 | 2403 | |
08f6fba5 | 2404 | case FTRACE_UPDATE_MODIFY_CALL: |
02a392a0 | 2405 | ftrace_bug_type = FTRACE_BUG_UPDATE; |
08f6fba5 | 2406 | return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); |
5072c59f SR |
2407 | } |
2408 | ||
c88fd863 | 2409 | return -1; /* unknow ftrace bug */ |
5072c59f SR |
2410 | } |
2411 | ||
e4f5d544 | 2412 | void __weak ftrace_replace_code(int enable) |
3c1720f0 | 2413 | { |
3c1720f0 SR |
2414 | struct dyn_ftrace *rec; |
2415 | struct ftrace_page *pg; | |
6a24a244 | 2416 | int failed; |
3c1720f0 | 2417 | |
45a4a237 SR |
2418 | if (unlikely(ftrace_disabled)) |
2419 | return; | |
2420 | ||
265c831c | 2421 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
2422 | |
2423 | if (rec->flags & FTRACE_FL_DISABLED) | |
2424 | continue; | |
2425 | ||
e4f5d544 | 2426 | failed = __ftrace_replace_code(rec, enable); |
fa9d13cf | 2427 | if (failed) { |
4fd3279b | 2428 | ftrace_bug(failed, rec); |
3279ba37 SR |
2429 | /* Stop processing */ |
2430 | return; | |
3c1720f0 | 2431 | } |
265c831c | 2432 | } while_for_each_ftrace_rec(); |
3c1720f0 SR |
2433 | } |
2434 | ||
c88fd863 SR |
2435 | struct ftrace_rec_iter { |
2436 | struct ftrace_page *pg; | |
2437 | int index; | |
2438 | }; | |
2439 | ||
2440 | /** | |
2441 | * ftrace_rec_iter_start, start up iterating over traced functions | |
2442 | * | |
2443 | * Returns an iterator handle that is used to iterate over all | |
2444 | * the records that represent address locations where functions | |
2445 | * are traced. | |
2446 | * | |
2447 | * May return NULL if no records are available. | |
2448 | */ | |
2449 | struct ftrace_rec_iter *ftrace_rec_iter_start(void) | |
2450 | { | |
2451 | /* | |
2452 | * We only use a single iterator. | |
2453 | * Protected by the ftrace_lock mutex. | |
2454 | */ | |
2455 | static struct ftrace_rec_iter ftrace_rec_iter; | |
2456 | struct ftrace_rec_iter *iter = &ftrace_rec_iter; | |
2457 | ||
2458 | iter->pg = ftrace_pages_start; | |
2459 | iter->index = 0; | |
2460 | ||
2461 | /* Could have empty pages */ | |
2462 | while (iter->pg && !iter->pg->index) | |
2463 | iter->pg = iter->pg->next; | |
2464 | ||
2465 | if (!iter->pg) | |
2466 | return NULL; | |
2467 | ||
2468 | return iter; | |
2469 | } | |
2470 | ||
2471 | /** | |
2472 | * ftrace_rec_iter_next, get the next record to process. | |
2473 | * @iter: The handle to the iterator. | |
2474 | * | |
2475 | * Returns the next iterator after the given iterator @iter. | |
2476 | */ | |
2477 | struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter) | |
2478 | { | |
2479 | iter->index++; | |
2480 | ||
2481 | if (iter->index >= iter->pg->index) { | |
2482 | iter->pg = iter->pg->next; | |
2483 | iter->index = 0; | |
2484 | ||
2485 | /* Could have empty pages */ | |
2486 | while (iter->pg && !iter->pg->index) | |
2487 | iter->pg = iter->pg->next; | |
2488 | } | |
2489 | ||
2490 | if (!iter->pg) | |
2491 | return NULL; | |
2492 | ||
2493 | return iter; | |
2494 | } | |
2495 | ||
2496 | /** | |
2497 | * ftrace_rec_iter_record, get the record at the iterator location | |
2498 | * @iter: The current iterator location | |
2499 | * | |
2500 | * Returns the record that the current @iter is at. | |
2501 | */ | |
2502 | struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter) | |
2503 | { | |
2504 | return &iter->pg->records[iter->index]; | |
2505 | } | |
2506 | ||
492a7ea5 | 2507 | static int |
31e88909 | 2508 | ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) |
3c1720f0 | 2509 | { |
593eb8a2 | 2510 | int ret; |
3c1720f0 | 2511 | |
45a4a237 SR |
2512 | if (unlikely(ftrace_disabled)) |
2513 | return 0; | |
2514 | ||
25aac9dc | 2515 | ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); |
593eb8a2 | 2516 | if (ret) { |
02a392a0 | 2517 | ftrace_bug_type = FTRACE_BUG_INIT; |
4fd3279b | 2518 | ftrace_bug(ret, rec); |
492a7ea5 | 2519 | return 0; |
37ad5084 | 2520 | } |
492a7ea5 | 2521 | return 1; |
3c1720f0 SR |
2522 | } |
2523 | ||
000ab691 SR |
2524 | /* |
2525 | * archs can override this function if they must do something | |
2526 | * before the modifying code is performed. | |
2527 | */ | |
2528 | int __weak ftrace_arch_code_modify_prepare(void) | |
2529 | { | |
2530 | return 0; | |
2531 | } | |
2532 | ||
2533 | /* | |
2534 | * archs can override this function if they must do something | |
2535 | * after the modifying code is performed. | |
2536 | */ | |
2537 | int __weak ftrace_arch_code_modify_post_process(void) | |
2538 | { | |
2539 | return 0; | |
2540 | } | |
2541 | ||
8ed3e2cf | 2542 | void ftrace_modify_all_code(int command) |
3d083395 | 2543 | { |
59338f75 | 2544 | int update = command & FTRACE_UPDATE_TRACE_FUNC; |
cd21067f | 2545 | int err = 0; |
59338f75 SRRH |
2546 | |
2547 | /* | |
2548 | * If the ftrace_caller calls a ftrace_ops func directly, | |
2549 | * we need to make sure that it only traces functions it | |
2550 | * expects to trace. When doing the switch of functions, | |
2551 | * we need to update to the ftrace_ops_list_func first | |
2552 | * before the transition between old and new calls are set, | |
2553 | * as the ftrace_ops_list_func will check the ops hashes | |
2554 | * to make sure the ops are having the right functions | |
2555 | * traced. | |
2556 | */ | |
cd21067f PM |
2557 | if (update) { |
2558 | err = ftrace_update_ftrace_func(ftrace_ops_list_func); | |
2559 | if (FTRACE_WARN_ON(err)) | |
2560 | return; | |
2561 | } | |
59338f75 | 2562 | |
8ed3e2cf | 2563 | if (command & FTRACE_UPDATE_CALLS) |
d61f82d0 | 2564 | ftrace_replace_code(1); |
8ed3e2cf | 2565 | else if (command & FTRACE_DISABLE_CALLS) |
d61f82d0 SR |
2566 | ftrace_replace_code(0); |
2567 | ||
405e1d83 SRRH |
2568 | if (update && ftrace_trace_function != ftrace_ops_list_func) { |
2569 | function_trace_op = set_function_trace_op; | |
2570 | smp_wmb(); | |
2571 | /* If irqs are disabled, we are in stop machine */ | |
2572 | if (!irqs_disabled()) | |
2573 | smp_call_function(ftrace_sync_ipi, NULL, 1); | |
cd21067f PM |
2574 | err = ftrace_update_ftrace_func(ftrace_trace_function); |
2575 | if (FTRACE_WARN_ON(err)) | |
2576 | return; | |
405e1d83 | 2577 | } |
d61f82d0 | 2578 | |
8ed3e2cf | 2579 | if (command & FTRACE_START_FUNC_RET) |
cd21067f | 2580 | err = ftrace_enable_ftrace_graph_caller(); |
8ed3e2cf | 2581 | else if (command & FTRACE_STOP_FUNC_RET) |
cd21067f PM |
2582 | err = ftrace_disable_ftrace_graph_caller(); |
2583 | FTRACE_WARN_ON(err); | |
8ed3e2cf SR |
2584 | } |
2585 | ||
2586 | static int __ftrace_modify_code(void *data) | |
2587 | { | |
2588 | int *command = data; | |
2589 | ||
2590 | ftrace_modify_all_code(*command); | |
5a45cfe1 | 2591 | |
d61f82d0 | 2592 | return 0; |
3d083395 SR |
2593 | } |
2594 | ||
c88fd863 SR |
2595 | /** |
2596 | * ftrace_run_stop_machine, go back to the stop machine method | |
2597 | * @command: The command to tell ftrace what to do | |
2598 | * | |
2599 | * If an arch needs to fall back to the stop machine method, the | |
2600 | * it can call this function. | |
2601 | */ | |
2602 | void ftrace_run_stop_machine(int command) | |
2603 | { | |
2604 | stop_machine(__ftrace_modify_code, &command, NULL); | |
2605 | } | |
2606 | ||
2607 | /** | |
2608 | * arch_ftrace_update_code, modify the code to trace or not trace | |
2609 | * @command: The command that needs to be done | |
2610 | * | |
2611 | * Archs can override this function if it does not need to | |
2612 | * run stop_machine() to modify code. | |
2613 | */ | |
2614 | void __weak arch_ftrace_update_code(int command) | |
2615 | { | |
2616 | ftrace_run_stop_machine(command); | |
2617 | } | |
2618 | ||
e309b41d | 2619 | static void ftrace_run_update_code(int command) |
3d083395 | 2620 | { |
000ab691 SR |
2621 | int ret; |
2622 | ||
2623 | ret = ftrace_arch_code_modify_prepare(); | |
2624 | FTRACE_WARN_ON(ret); | |
2625 | if (ret) | |
2626 | return; | |
2627 | ||
c88fd863 SR |
2628 | /* |
2629 | * By default we use stop_machine() to modify the code. | |
2630 | * But archs can do what ever they want as long as it | |
2631 | * is safe. The stop_machine() is the safest, but also | |
2632 | * produces the most overhead. | |
2633 | */ | |
2634 | arch_ftrace_update_code(command); | |
2635 | ||
000ab691 SR |
2636 | ret = ftrace_arch_code_modify_post_process(); |
2637 | FTRACE_WARN_ON(ret); | |
3d083395 SR |
2638 | } |
2639 | ||
8252ecf3 | 2640 | static void ftrace_run_modify_code(struct ftrace_ops *ops, int command, |
7485058e | 2641 | struct ftrace_ops_hash *old_hash) |
e1effa01 SRRH |
2642 | { |
2643 | ops->flags |= FTRACE_OPS_FL_MODIFYING; | |
7485058e SRRH |
2644 | ops->old_hash.filter_hash = old_hash->filter_hash; |
2645 | ops->old_hash.notrace_hash = old_hash->notrace_hash; | |
e1effa01 | 2646 | ftrace_run_update_code(command); |
8252ecf3 | 2647 | ops->old_hash.filter_hash = NULL; |
7485058e | 2648 | ops->old_hash.notrace_hash = NULL; |
e1effa01 SRRH |
2649 | ops->flags &= ~FTRACE_OPS_FL_MODIFYING; |
2650 | } | |
2651 | ||
d61f82d0 | 2652 | static ftrace_func_t saved_ftrace_func; |
60a7ecf4 | 2653 | static int ftrace_start_up; |
df4fc315 | 2654 | |
12cce594 SRRH |
2655 | void __weak arch_ftrace_trampoline_free(struct ftrace_ops *ops) |
2656 | { | |
2657 | } | |
2658 | ||
ba27f2bc | 2659 | static void per_cpu_ops_free(struct ftrace_ops *ops) |
db0fbadc JS |
2660 | { |
2661 | free_percpu(ops->disabled); | |
2662 | } | |
2663 | ||
df4fc315 SR |
2664 | static void ftrace_startup_enable(int command) |
2665 | { | |
2666 | if (saved_ftrace_func != ftrace_trace_function) { | |
2667 | saved_ftrace_func = ftrace_trace_function; | |
2668 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2669 | } | |
2670 | ||
2671 | if (!command || !ftrace_enabled) | |
2672 | return; | |
2673 | ||
2674 | ftrace_run_update_code(command); | |
2675 | } | |
d61f82d0 | 2676 | |
e1effa01 SRRH |
2677 | static void ftrace_startup_all(int command) |
2678 | { | |
2679 | update_all_ops = true; | |
2680 | ftrace_startup_enable(command); | |
2681 | update_all_ops = false; | |
2682 | } | |
2683 | ||
a1cd6173 | 2684 | static int ftrace_startup(struct ftrace_ops *ops, int command) |
3d083395 | 2685 | { |
8a56d776 | 2686 | int ret; |
b848914c | 2687 | |
4eebcc81 | 2688 | if (unlikely(ftrace_disabled)) |
a1cd6173 | 2689 | return -ENODEV; |
4eebcc81 | 2690 | |
8a56d776 SRRH |
2691 | ret = __register_ftrace_function(ops); |
2692 | if (ret) | |
2693 | return ret; | |
2694 | ||
60a7ecf4 | 2695 | ftrace_start_up++; |
d61f82d0 | 2696 | |
e1effa01 SRRH |
2697 | /* |
2698 | * Note that ftrace probes uses this to start up | |
2699 | * and modify functions it will probe. But we still | |
2700 | * set the ADDING flag for modification, as probes | |
2701 | * do not have trampolines. If they add them in the | |
2702 | * future, then the probes will need to distinguish | |
2703 | * between adding and updating probes. | |
2704 | */ | |
2705 | ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING; | |
66209a5b | 2706 | |
f8b8be8a MH |
2707 | ret = ftrace_hash_ipmodify_enable(ops); |
2708 | if (ret < 0) { | |
2709 | /* Rollback registration process */ | |
2710 | __unregister_ftrace_function(ops); | |
2711 | ftrace_start_up--; | |
2712 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; | |
2713 | return ret; | |
2714 | } | |
2715 | ||
7f50d06b JO |
2716 | if (ftrace_hash_rec_enable(ops, 1)) |
2717 | command |= FTRACE_UPDATE_CALLS; | |
ed926f9b | 2718 | |
df4fc315 | 2719 | ftrace_startup_enable(command); |
a1cd6173 | 2720 | |
e1effa01 SRRH |
2721 | ops->flags &= ~FTRACE_OPS_FL_ADDING; |
2722 | ||
a1cd6173 | 2723 | return 0; |
3d083395 SR |
2724 | } |
2725 | ||
8a56d776 | 2726 | static int ftrace_shutdown(struct ftrace_ops *ops, int command) |
3d083395 | 2727 | { |
8a56d776 | 2728 | int ret; |
b848914c | 2729 | |
4eebcc81 | 2730 | if (unlikely(ftrace_disabled)) |
8a56d776 SRRH |
2731 | return -ENODEV; |
2732 | ||
2733 | ret = __unregister_ftrace_function(ops); | |
2734 | if (ret) | |
2735 | return ret; | |
4eebcc81 | 2736 | |
60a7ecf4 | 2737 | ftrace_start_up--; |
9ea1a153 FW |
2738 | /* |
2739 | * Just warn in case of unbalance, no need to kill ftrace, it's not | |
2740 | * critical but the ftrace_call callers may be never nopped again after | |
2741 | * further ftrace uses. | |
2742 | */ | |
2743 | WARN_ON_ONCE(ftrace_start_up < 0); | |
2744 | ||
f8b8be8a MH |
2745 | /* Disabling ipmodify never fails */ |
2746 | ftrace_hash_ipmodify_disable(ops); | |
ed926f9b | 2747 | |
7f50d06b JO |
2748 | if (ftrace_hash_rec_disable(ops, 1)) |
2749 | command |= FTRACE_UPDATE_CALLS; | |
b848914c | 2750 | |
7f50d06b | 2751 | ops->flags &= ~FTRACE_OPS_FL_ENABLED; |
3d083395 | 2752 | |
d61f82d0 SR |
2753 | if (saved_ftrace_func != ftrace_trace_function) { |
2754 | saved_ftrace_func = ftrace_trace_function; | |
2755 | command |= FTRACE_UPDATE_TRACE_FUNC; | |
2756 | } | |
3d083395 | 2757 | |
a4c35ed2 SRRH |
2758 | if (!command || !ftrace_enabled) { |
2759 | /* | |
ba27f2bc | 2760 | * If these are per_cpu ops, they still need their |
a4c35ed2 SRRH |
2761 | * per_cpu field freed. Since, function tracing is |
2762 | * not currently active, we can just free them | |
2763 | * without synchronizing all CPUs. | |
2764 | */ | |
ba27f2bc SRRH |
2765 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) |
2766 | per_cpu_ops_free(ops); | |
8a56d776 | 2767 | return 0; |
a4c35ed2 | 2768 | } |
d61f82d0 | 2769 | |
79922b80 SRRH |
2770 | /* |
2771 | * If the ops uses a trampoline, then it needs to be | |
2772 | * tested first on update. | |
2773 | */ | |
e1effa01 | 2774 | ops->flags |= FTRACE_OPS_FL_REMOVING; |
79922b80 SRRH |
2775 | removed_ops = ops; |
2776 | ||
fef5aeee SRRH |
2777 | /* The trampoline logic checks the old hashes */ |
2778 | ops->old_hash.filter_hash = ops->func_hash->filter_hash; | |
2779 | ops->old_hash.notrace_hash = ops->func_hash->notrace_hash; | |
2780 | ||
d61f82d0 | 2781 | ftrace_run_update_code(command); |
a4c35ed2 | 2782 | |
84bde62c SRRH |
2783 | /* |
2784 | * If there's no more ops registered with ftrace, run a | |
2785 | * sanity check to make sure all rec flags are cleared. | |
2786 | */ | |
2787 | if (ftrace_ops_list == &ftrace_list_end) { | |
2788 | struct ftrace_page *pg; | |
2789 | struct dyn_ftrace *rec; | |
2790 | ||
2791 | do_for_each_ftrace_rec(pg, rec) { | |
977c1f9c | 2792 | if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED)) |
84bde62c SRRH |
2793 | pr_warn(" %pS flags:%lx\n", |
2794 | (void *)rec->ip, rec->flags); | |
2795 | } while_for_each_ftrace_rec(); | |
2796 | } | |
2797 | ||
fef5aeee SRRH |
2798 | ops->old_hash.filter_hash = NULL; |
2799 | ops->old_hash.notrace_hash = NULL; | |
2800 | ||
2801 | removed_ops = NULL; | |
e1effa01 | 2802 | ops->flags &= ~FTRACE_OPS_FL_REMOVING; |
79922b80 | 2803 | |
a4c35ed2 SRRH |
2804 | /* |
2805 | * Dynamic ops may be freed, we must make sure that all | |
2806 | * callers are done before leaving this function. | |
ba27f2bc | 2807 | * The same goes for freeing the per_cpu data of the per_cpu |
a4c35ed2 SRRH |
2808 | * ops. |
2809 | * | |
2810 | * Again, normal synchronize_sched() is not good enough. | |
2811 | * We need to do a hard force of sched synchronization. | |
2812 | * This is because we use preempt_disable() to do RCU, but | |
2813 | * the function tracers can be called where RCU is not watching | |
2814 | * (like before user_exit()). We can not rely on the RCU | |
2815 | * infrastructure to do the synchronization, thus we must do it | |
2816 | * ourselves. | |
2817 | */ | |
ba27f2bc | 2818 | if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_PER_CPU)) { |
a4c35ed2 SRRH |
2819 | schedule_on_each_cpu(ftrace_sync); |
2820 | ||
12cce594 SRRH |
2821 | arch_ftrace_trampoline_free(ops); |
2822 | ||
ba27f2bc SRRH |
2823 | if (ops->flags & FTRACE_OPS_FL_PER_CPU) |
2824 | per_cpu_ops_free(ops); | |
a4c35ed2 SRRH |
2825 | } |
2826 | ||
8a56d776 | 2827 | return 0; |
3d083395 SR |
2828 | } |
2829 | ||
e309b41d | 2830 | static void ftrace_startup_sysctl(void) |
b0fc494f | 2831 | { |
1619dc3f PA |
2832 | int command; |
2833 | ||
4eebcc81 SR |
2834 | if (unlikely(ftrace_disabled)) |
2835 | return; | |
2836 | ||
d61f82d0 SR |
2837 | /* Force update next time */ |
2838 | saved_ftrace_func = NULL; | |
60a7ecf4 | 2839 | /* ftrace_start_up is true if we want ftrace running */ |
1619dc3f PA |
2840 | if (ftrace_start_up) { |
2841 | command = FTRACE_UPDATE_CALLS; | |
2842 | if (ftrace_graph_active) | |
2843 | command |= FTRACE_START_FUNC_RET; | |
524a3868 | 2844 | ftrace_startup_enable(command); |
1619dc3f | 2845 | } |
b0fc494f SR |
2846 | } |
2847 | ||
e309b41d | 2848 | static void ftrace_shutdown_sysctl(void) |
b0fc494f | 2849 | { |
1619dc3f PA |
2850 | int command; |
2851 | ||
4eebcc81 SR |
2852 | if (unlikely(ftrace_disabled)) |
2853 | return; | |
2854 | ||
60a7ecf4 | 2855 | /* ftrace_start_up is true if ftrace is running */ |
1619dc3f PA |
2856 | if (ftrace_start_up) { |
2857 | command = FTRACE_DISABLE_CALLS; | |
2858 | if (ftrace_graph_active) | |
2859 | command |= FTRACE_STOP_FUNC_RET; | |
2860 | ftrace_run_update_code(command); | |
2861 | } | |
b0fc494f SR |
2862 | } |
2863 | ||
a5a1d1c2 | 2864 | static u64 ftrace_update_time; |
3d083395 SR |
2865 | unsigned long ftrace_update_tot_cnt; |
2866 | ||
8c4f3c3f | 2867 | static inline int ops_traces_mod(struct ftrace_ops *ops) |
f7bc8b61 | 2868 | { |
8c4f3c3f SRRH |
2869 | /* |
2870 | * Filter_hash being empty will default to trace module. | |
2871 | * But notrace hash requires a test of individual module functions. | |
2872 | */ | |
33b7f99c SRRH |
2873 | return ftrace_hash_empty(ops->func_hash->filter_hash) && |
2874 | ftrace_hash_empty(ops->func_hash->notrace_hash); | |
8c4f3c3f SRRH |
2875 | } |
2876 | ||
2877 | /* | |
2878 | * Check if the current ops references the record. | |
2879 | * | |
2880 | * If the ops traces all functions, then it was already accounted for. | |
2881 | * If the ops does not trace the current record function, skip it. | |
2882 | * If the ops ignores the function via notrace filter, skip it. | |
2883 | */ | |
2884 | static inline bool | |
2885 | ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
2886 | { | |
2887 | /* If ops isn't enabled, ignore it */ | |
2888 | if (!(ops->flags & FTRACE_OPS_FL_ENABLED)) | |
2889 | return 0; | |
2890 | ||
b7ffffbb | 2891 | /* If ops traces all then it includes this function */ |
8c4f3c3f | 2892 | if (ops_traces_mod(ops)) |
b7ffffbb | 2893 | return 1; |
8c4f3c3f SRRH |
2894 | |
2895 | /* The function must be in the filter */ | |
33b7f99c | 2896 | if (!ftrace_hash_empty(ops->func_hash->filter_hash) && |
2b2c279c | 2897 | !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) |
8c4f3c3f | 2898 | return 0; |
f7bc8b61 | 2899 | |
8c4f3c3f | 2900 | /* If in notrace hash, we ignore it too */ |
33b7f99c | 2901 | if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) |
8c4f3c3f SRRH |
2902 | return 0; |
2903 | ||
2904 | return 1; | |
2905 | } | |
2906 | ||
1dc43cf0 | 2907 | static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) |
3d083395 | 2908 | { |
85ae32ae | 2909 | struct ftrace_page *pg; |
e94142a6 | 2910 | struct dyn_ftrace *p; |
a5a1d1c2 | 2911 | u64 start, stop; |
1dc43cf0 | 2912 | unsigned long update_cnt = 0; |
b7ffffbb | 2913 | unsigned long rec_flags = 0; |
85ae32ae | 2914 | int i; |
f7bc8b61 | 2915 | |
b7ffffbb SRRH |
2916 | start = ftrace_now(raw_smp_processor_id()); |
2917 | ||
f7bc8b61 | 2918 | /* |
b7ffffbb SRRH |
2919 | * When a module is loaded, this function is called to convert |
2920 | * the calls to mcount in its text to nops, and also to create | |
2921 | * an entry in the ftrace data. Now, if ftrace is activated | |
2922 | * after this call, but before the module sets its text to | |
2923 | * read-only, the modification of enabling ftrace can fail if | |
2924 | * the read-only is done while ftrace is converting the calls. | |
2925 | * To prevent this, the module's records are set as disabled | |
2926 | * and will be enabled after the call to set the module's text | |
2927 | * to read-only. | |
f7bc8b61 | 2928 | */ |
b7ffffbb SRRH |
2929 | if (mod) |
2930 | rec_flags |= FTRACE_FL_DISABLED; | |
3d083395 | 2931 | |
1dc43cf0 | 2932 | for (pg = new_pgs; pg; pg = pg->next) { |
3d083395 | 2933 | |
85ae32ae | 2934 | for (i = 0; i < pg->index; i++) { |
8c4f3c3f | 2935 | |
85ae32ae SR |
2936 | /* If something went wrong, bail without enabling anything */ |
2937 | if (unlikely(ftrace_disabled)) | |
2938 | return -1; | |
f22f9a89 | 2939 | |
85ae32ae | 2940 | p = &pg->records[i]; |
b7ffffbb | 2941 | p->flags = rec_flags; |
f22f9a89 | 2942 | |
85ae32ae SR |
2943 | /* |
2944 | * Do the initial record conversion from mcount jump | |
2945 | * to the NOP instructions. | |
2946 | */ | |
2947 | if (!ftrace_code_disable(mod, p)) | |
2948 | break; | |
5cb084bb | 2949 | |
1dc43cf0 | 2950 | update_cnt++; |
5cb084bb | 2951 | } |
3d083395 SR |
2952 | } |
2953 | ||
750ed1a4 | 2954 | stop = ftrace_now(raw_smp_processor_id()); |
3d083395 | 2955 | ftrace_update_time = stop - start; |
1dc43cf0 | 2956 | ftrace_update_tot_cnt += update_cnt; |
3d083395 | 2957 | |
16444a8a ACM |
2958 | return 0; |
2959 | } | |
2960 | ||
a7900875 | 2961 | static int ftrace_allocate_records(struct ftrace_page *pg, int count) |
3c1720f0 | 2962 | { |
a7900875 | 2963 | int order; |
3c1720f0 | 2964 | int cnt; |
3c1720f0 | 2965 | |
a7900875 SR |
2966 | if (WARN_ON(!count)) |
2967 | return -EINVAL; | |
2968 | ||
2969 | order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE)); | |
3c1720f0 SR |
2970 | |
2971 | /* | |
a7900875 SR |
2972 | * We want to fill as much as possible. No more than a page |
2973 | * may be empty. | |
3c1720f0 | 2974 | */ |
a7900875 SR |
2975 | while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE) |
2976 | order--; | |
3c1720f0 | 2977 | |
a7900875 SR |
2978 | again: |
2979 | pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); | |
3c1720f0 | 2980 | |
a7900875 SR |
2981 | if (!pg->records) { |
2982 | /* if we can't allocate this size, try something smaller */ | |
2983 | if (!order) | |
2984 | return -ENOMEM; | |
2985 | order >>= 1; | |
2986 | goto again; | |
2987 | } | |
3c1720f0 | 2988 | |
a7900875 SR |
2989 | cnt = (PAGE_SIZE << order) / ENTRY_SIZE; |
2990 | pg->size = cnt; | |
3c1720f0 | 2991 | |
a7900875 SR |
2992 | if (cnt > count) |
2993 | cnt = count; | |
2994 | ||
2995 | return cnt; | |
2996 | } | |
2997 | ||
2998 | static struct ftrace_page * | |
2999 | ftrace_allocate_pages(unsigned long num_to_init) | |
3000 | { | |
3001 | struct ftrace_page *start_pg; | |
3002 | struct ftrace_page *pg; | |
3003 | int order; | |
3004 | int cnt; | |
3005 | ||
3006 | if (!num_to_init) | |
3007 | return 0; | |
3008 | ||
3009 | start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL); | |
3010 | if (!pg) | |
3011 | return NULL; | |
3012 | ||
3013 | /* | |
3014 | * Try to allocate as much as possible in one continues | |
3015 | * location that fills in all of the space. We want to | |
3016 | * waste as little space as possible. | |
3017 | */ | |
3018 | for (;;) { | |
3019 | cnt = ftrace_allocate_records(pg, num_to_init); | |
3020 | if (cnt < 0) | |
3021 | goto free_pages; | |
3022 | ||
3023 | num_to_init -= cnt; | |
3024 | if (!num_to_init) | |
3c1720f0 SR |
3025 | break; |
3026 | ||
a7900875 SR |
3027 | pg->next = kzalloc(sizeof(*pg), GFP_KERNEL); |
3028 | if (!pg->next) | |
3029 | goto free_pages; | |
3030 | ||
3c1720f0 SR |
3031 | pg = pg->next; |
3032 | } | |
3033 | ||
a7900875 SR |
3034 | return start_pg; |
3035 | ||
3036 | free_pages: | |
1f61be00 NK |
3037 | pg = start_pg; |
3038 | while (pg) { | |
a7900875 SR |
3039 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
3040 | free_pages((unsigned long)pg->records, order); | |
3041 | start_pg = pg->next; | |
3042 | kfree(pg); | |
3043 | pg = start_pg; | |
3044 | } | |
3045 | pr_info("ftrace: FAILED to allocate memory for functions\n"); | |
3046 | return NULL; | |
3047 | } | |
3048 | ||
5072c59f SR |
3049 | #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */ |
3050 | ||
3051 | struct ftrace_iterator { | |
98c4fd04 | 3052 | loff_t pos; |
4aeb6967 SR |
3053 | loff_t func_pos; |
3054 | struct ftrace_page *pg; | |
3055 | struct dyn_ftrace *func; | |
3056 | struct ftrace_func_probe *probe; | |
3057 | struct trace_parser parser; | |
1cf41dd7 | 3058 | struct ftrace_hash *hash; |
33dc9b12 | 3059 | struct ftrace_ops *ops; |
4aeb6967 SR |
3060 | int hidx; |
3061 | int idx; | |
3062 | unsigned flags; | |
5072c59f SR |
3063 | }; |
3064 | ||
8fc0c701 | 3065 | static void * |
4aeb6967 | 3066 | t_hash_next(struct seq_file *m, loff_t *pos) |
8fc0c701 SR |
3067 | { |
3068 | struct ftrace_iterator *iter = m->private; | |
4aeb6967 | 3069 | struct hlist_node *hnd = NULL; |
8fc0c701 SR |
3070 | struct hlist_head *hhd; |
3071 | ||
8fc0c701 | 3072 | (*pos)++; |
98c4fd04 | 3073 | iter->pos = *pos; |
8fc0c701 | 3074 | |
4aeb6967 SR |
3075 | if (iter->probe) |
3076 | hnd = &iter->probe->node; | |
8fc0c701 SR |
3077 | retry: |
3078 | if (iter->hidx >= FTRACE_FUNC_HASHSIZE) | |
3079 | return NULL; | |
3080 | ||
3081 | hhd = &ftrace_func_hash[iter->hidx]; | |
3082 | ||
3083 | if (hlist_empty(hhd)) { | |
3084 | iter->hidx++; | |
3085 | hnd = NULL; | |
3086 | goto retry; | |
3087 | } | |
3088 | ||
3089 | if (!hnd) | |
3090 | hnd = hhd->first; | |
3091 | else { | |
3092 | hnd = hnd->next; | |
3093 | if (!hnd) { | |
3094 | iter->hidx++; | |
3095 | goto retry; | |
3096 | } | |
3097 | } | |
3098 | ||
4aeb6967 SR |
3099 | if (WARN_ON_ONCE(!hnd)) |
3100 | return NULL; | |
3101 | ||
3102 | iter->probe = hlist_entry(hnd, struct ftrace_func_probe, node); | |
3103 | ||
3104 | return iter; | |
8fc0c701 SR |
3105 | } |
3106 | ||
3107 | static void *t_hash_start(struct seq_file *m, loff_t *pos) | |
3108 | { | |
3109 | struct ftrace_iterator *iter = m->private; | |
3110 | void *p = NULL; | |
d82d6244 LZ |
3111 | loff_t l; |
3112 | ||
69a3083c SR |
3113 | if (!(iter->flags & FTRACE_ITER_DO_HASH)) |
3114 | return NULL; | |
3115 | ||
2bccfffd SR |
3116 | if (iter->func_pos > *pos) |
3117 | return NULL; | |
8fc0c701 | 3118 | |
d82d6244 | 3119 | iter->hidx = 0; |
2bccfffd | 3120 | for (l = 0; l <= (*pos - iter->func_pos); ) { |
4aeb6967 | 3121 | p = t_hash_next(m, &l); |
d82d6244 LZ |
3122 | if (!p) |
3123 | break; | |
3124 | } | |
4aeb6967 SR |
3125 | if (!p) |
3126 | return NULL; | |
3127 | ||
98c4fd04 SR |
3128 | /* Only set this if we have an item */ |
3129 | iter->flags |= FTRACE_ITER_HASH; | |
3130 | ||
4aeb6967 | 3131 | return iter; |
8fc0c701 SR |
3132 | } |
3133 | ||
4aeb6967 SR |
3134 | static int |
3135 | t_hash_show(struct seq_file *m, struct ftrace_iterator *iter) | |
8fc0c701 | 3136 | { |
b6887d79 | 3137 | struct ftrace_func_probe *rec; |
8fc0c701 | 3138 | |
4aeb6967 SR |
3139 | rec = iter->probe; |
3140 | if (WARN_ON_ONCE(!rec)) | |
3141 | return -EIO; | |
8fc0c701 | 3142 | |
809dcf29 SR |
3143 | if (rec->ops->print) |
3144 | return rec->ops->print(m, rec->ip, rec->ops, rec->data); | |
3145 | ||
b375a11a | 3146 | seq_printf(m, "%ps:%ps", (void *)rec->ip, (void *)rec->ops->func); |
8fc0c701 SR |
3147 | |
3148 | if (rec->data) | |
3149 | seq_printf(m, ":%p", rec->data); | |
3150 | seq_putc(m, '\n'); | |
3151 | ||
3152 | return 0; | |
3153 | } | |
3154 | ||
e309b41d | 3155 | static void * |
5072c59f SR |
3156 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3157 | { | |
3158 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 3159 | struct ftrace_ops *ops = iter->ops; |
5072c59f SR |
3160 | struct dyn_ftrace *rec = NULL; |
3161 | ||
45a4a237 SR |
3162 | if (unlikely(ftrace_disabled)) |
3163 | return NULL; | |
3164 | ||
8fc0c701 | 3165 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 3166 | return t_hash_next(m, pos); |
8fc0c701 | 3167 | |
5072c59f | 3168 | (*pos)++; |
1106b699 | 3169 | iter->pos = iter->func_pos = *pos; |
5072c59f | 3170 | |
0c75a3ed | 3171 | if (iter->flags & FTRACE_ITER_PRINTALL) |
57c072c7 | 3172 | return t_hash_start(m, pos); |
0c75a3ed | 3173 | |
5072c59f SR |
3174 | retry: |
3175 | if (iter->idx >= iter->pg->index) { | |
3176 | if (iter->pg->next) { | |
3177 | iter->pg = iter->pg->next; | |
3178 | iter->idx = 0; | |
3179 | goto retry; | |
3180 | } | |
3181 | } else { | |
3182 | rec = &iter->pg->records[iter->idx++]; | |
32082309 | 3183 | if (((iter->flags & FTRACE_ITER_FILTER) && |
33b7f99c | 3184 | !(ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip))) || |
0183fb1c | 3185 | |
41c52c0d | 3186 | ((iter->flags & FTRACE_ITER_NOTRACE) && |
33b7f99c | 3187 | !ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip)) || |
647bcd03 SR |
3188 | |
3189 | ((iter->flags & FTRACE_ITER_ENABLED) && | |
23ea9c4d | 3190 | !(rec->flags & FTRACE_FL_ENABLED))) { |
647bcd03 | 3191 | |
5072c59f SR |
3192 | rec = NULL; |
3193 | goto retry; | |
3194 | } | |
3195 | } | |
3196 | ||
4aeb6967 | 3197 | if (!rec) |
57c072c7 | 3198 | return t_hash_start(m, pos); |
4aeb6967 SR |
3199 | |
3200 | iter->func = rec; | |
3201 | ||
3202 | return iter; | |
5072c59f SR |
3203 | } |
3204 | ||
98c4fd04 SR |
3205 | static void reset_iter_read(struct ftrace_iterator *iter) |
3206 | { | |
3207 | iter->pos = 0; | |
3208 | iter->func_pos = 0; | |
70f77b3f | 3209 | iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_HASH); |
5072c59f SR |
3210 | } |
3211 | ||
3212 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3213 | { | |
3214 | struct ftrace_iterator *iter = m->private; | |
fc13cb0c | 3215 | struct ftrace_ops *ops = iter->ops; |
5072c59f | 3216 | void *p = NULL; |
694ce0a5 | 3217 | loff_t l; |
5072c59f | 3218 | |
8fc0c701 | 3219 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
3220 | |
3221 | if (unlikely(ftrace_disabled)) | |
3222 | return NULL; | |
3223 | ||
98c4fd04 SR |
3224 | /* |
3225 | * If an lseek was done, then reset and start from beginning. | |
3226 | */ | |
3227 | if (*pos < iter->pos) | |
3228 | reset_iter_read(iter); | |
3229 | ||
0c75a3ed SR |
3230 | /* |
3231 | * For set_ftrace_filter reading, if we have the filter | |
3232 | * off, we can short cut and just print out that all | |
3233 | * functions are enabled. | |
3234 | */ | |
8c006cf7 | 3235 | if ((iter->flags & FTRACE_ITER_FILTER && |
33b7f99c | 3236 | ftrace_hash_empty(ops->func_hash->filter_hash)) || |
8c006cf7 | 3237 | (iter->flags & FTRACE_ITER_NOTRACE && |
33b7f99c | 3238 | ftrace_hash_empty(ops->func_hash->notrace_hash))) { |
0c75a3ed | 3239 | if (*pos > 0) |
8fc0c701 | 3240 | return t_hash_start(m, pos); |
0c75a3ed | 3241 | iter->flags |= FTRACE_ITER_PRINTALL; |
df091625 CW |
3242 | /* reset in case of seek/pread */ |
3243 | iter->flags &= ~FTRACE_ITER_HASH; | |
0c75a3ed SR |
3244 | return iter; |
3245 | } | |
3246 | ||
8fc0c701 SR |
3247 | if (iter->flags & FTRACE_ITER_HASH) |
3248 | return t_hash_start(m, pos); | |
3249 | ||
98c4fd04 SR |
3250 | /* |
3251 | * Unfortunately, we need to restart at ftrace_pages_start | |
3252 | * every time we let go of the ftrace_mutex. This is because | |
3253 | * those pointers can change without the lock. | |
3254 | */ | |
694ce0a5 LZ |
3255 | iter->pg = ftrace_pages_start; |
3256 | iter->idx = 0; | |
3257 | for (l = 0; l <= *pos; ) { | |
3258 | p = t_next(m, p, &l); | |
3259 | if (!p) | |
3260 | break; | |
50cdaf08 | 3261 | } |
5821e1b7 | 3262 | |
69a3083c SR |
3263 | if (!p) |
3264 | return t_hash_start(m, pos); | |
4aeb6967 SR |
3265 | |
3266 | return iter; | |
5072c59f SR |
3267 | } |
3268 | ||
3269 | static void t_stop(struct seq_file *m, void *p) | |
3270 | { | |
8fc0c701 | 3271 | mutex_unlock(&ftrace_lock); |
5072c59f SR |
3272 | } |
3273 | ||
15d5b02c SRRH |
3274 | void * __weak |
3275 | arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec) | |
3276 | { | |
3277 | return NULL; | |
3278 | } | |
3279 | ||
3280 | static void add_trampoline_func(struct seq_file *m, struct ftrace_ops *ops, | |
3281 | struct dyn_ftrace *rec) | |
3282 | { | |
3283 | void *ptr; | |
3284 | ||
3285 | ptr = arch_ftrace_trampoline_func(ops, rec); | |
3286 | if (ptr) | |
3287 | seq_printf(m, " ->%pS", ptr); | |
3288 | } | |
3289 | ||
5072c59f SR |
3290 | static int t_show(struct seq_file *m, void *v) |
3291 | { | |
0c75a3ed | 3292 | struct ftrace_iterator *iter = m->private; |
4aeb6967 | 3293 | struct dyn_ftrace *rec; |
5072c59f | 3294 | |
8fc0c701 | 3295 | if (iter->flags & FTRACE_ITER_HASH) |
4aeb6967 | 3296 | return t_hash_show(m, iter); |
8fc0c701 | 3297 | |
0c75a3ed | 3298 | if (iter->flags & FTRACE_ITER_PRINTALL) { |
8c006cf7 | 3299 | if (iter->flags & FTRACE_ITER_NOTRACE) |
fa6f0cc7 | 3300 | seq_puts(m, "#### no functions disabled ####\n"); |
8c006cf7 | 3301 | else |
fa6f0cc7 | 3302 | seq_puts(m, "#### all functions enabled ####\n"); |
0c75a3ed SR |
3303 | return 0; |
3304 | } | |
3305 | ||
4aeb6967 SR |
3306 | rec = iter->func; |
3307 | ||
5072c59f SR |
3308 | if (!rec) |
3309 | return 0; | |
3310 | ||
647bcd03 | 3311 | seq_printf(m, "%ps", (void *)rec->ip); |
9674b2fa | 3312 | if (iter->flags & FTRACE_ITER_ENABLED) { |
030f4e1c | 3313 | struct ftrace_ops *ops; |
15d5b02c | 3314 | |
f8b8be8a | 3315 | seq_printf(m, " (%ld)%s%s", |
0376bde1 | 3316 | ftrace_rec_count(rec), |
f8b8be8a MH |
3317 | rec->flags & FTRACE_FL_REGS ? " R" : " ", |
3318 | rec->flags & FTRACE_FL_IPMODIFY ? " I" : " "); | |
9674b2fa | 3319 | if (rec->flags & FTRACE_FL_TRAMP_EN) { |
5fecaa04 | 3320 | ops = ftrace_find_tramp_ops_any(rec); |
39daa7b9 SRRH |
3321 | if (ops) { |
3322 | do { | |
3323 | seq_printf(m, "\ttramp: %pS (%pS)", | |
3324 | (void *)ops->trampoline, | |
3325 | (void *)ops->func); | |
030f4e1c | 3326 | add_trampoline_func(m, ops, rec); |
39daa7b9 SRRH |
3327 | ops = ftrace_find_tramp_ops_next(rec, ops); |
3328 | } while (ops); | |
3329 | } else | |
fa6f0cc7 | 3330 | seq_puts(m, "\ttramp: ERROR!"); |
030f4e1c SRRH |
3331 | } else { |
3332 | add_trampoline_func(m, NULL, rec); | |
9674b2fa SRRH |
3333 | } |
3334 | } | |
3335 | ||
fa6f0cc7 | 3336 | seq_putc(m, '\n'); |
5072c59f SR |
3337 | |
3338 | return 0; | |
3339 | } | |
3340 | ||
88e9d34c | 3341 | static const struct seq_operations show_ftrace_seq_ops = { |
5072c59f SR |
3342 | .start = t_start, |
3343 | .next = t_next, | |
3344 | .stop = t_stop, | |
3345 | .show = t_show, | |
3346 | }; | |
3347 | ||
e309b41d | 3348 | static int |
5072c59f SR |
3349 | ftrace_avail_open(struct inode *inode, struct file *file) |
3350 | { | |
3351 | struct ftrace_iterator *iter; | |
5072c59f | 3352 | |
4eebcc81 SR |
3353 | if (unlikely(ftrace_disabled)) |
3354 | return -ENODEV; | |
3355 | ||
50e18b94 JO |
3356 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
3357 | if (iter) { | |
3358 | iter->pg = ftrace_pages_start; | |
3359 | iter->ops = &global_ops; | |
4bf39a94 | 3360 | } |
5072c59f | 3361 | |
50e18b94 | 3362 | return iter ? 0 : -ENOMEM; |
5072c59f SR |
3363 | } |
3364 | ||
647bcd03 SR |
3365 | static int |
3366 | ftrace_enabled_open(struct inode *inode, struct file *file) | |
3367 | { | |
3368 | struct ftrace_iterator *iter; | |
647bcd03 | 3369 | |
50e18b94 JO |
3370 | iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); |
3371 | if (iter) { | |
3372 | iter->pg = ftrace_pages_start; | |
3373 | iter->flags = FTRACE_ITER_ENABLED; | |
3374 | iter->ops = &global_ops; | |
647bcd03 SR |
3375 | } |
3376 | ||
50e18b94 | 3377 | return iter ? 0 : -ENOMEM; |
647bcd03 SR |
3378 | } |
3379 | ||
fc13cb0c SR |
3380 | /** |
3381 | * ftrace_regex_open - initialize function tracer filter files | |
3382 | * @ops: The ftrace_ops that hold the hash filters | |
3383 | * @flag: The type of filter to process | |
3384 | * @inode: The inode, usually passed in to your open routine | |
3385 | * @file: The file, usually passed in to your open routine | |
3386 | * | |
3387 | * ftrace_regex_open() initializes the filter files for the | |
3388 | * @ops. Depending on @flag it may process the filter hash or | |
3389 | * the notrace hash of @ops. With this called from the open | |
3390 | * routine, you can use ftrace_filter_write() for the write | |
3391 | * routine if @flag has FTRACE_ITER_FILTER set, or | |
3392 | * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. | |
098c879e | 3393 | * tracing_lseek() should be used as the lseek routine, and |
fc13cb0c SR |
3394 | * release must call ftrace_regex_release(). |
3395 | */ | |
3396 | int | |
f45948e8 | 3397 | ftrace_regex_open(struct ftrace_ops *ops, int flag, |
1cf41dd7 | 3398 | struct inode *inode, struct file *file) |
5072c59f SR |
3399 | { |
3400 | struct ftrace_iterator *iter; | |
f45948e8 | 3401 | struct ftrace_hash *hash; |
5072c59f SR |
3402 | int ret = 0; |
3403 | ||
f04f24fb MH |
3404 | ftrace_ops_init(ops); |
3405 | ||
4eebcc81 SR |
3406 | if (unlikely(ftrace_disabled)) |
3407 | return -ENODEV; | |
3408 | ||
5072c59f SR |
3409 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
3410 | if (!iter) | |
3411 | return -ENOMEM; | |
3412 | ||
689fd8b6 | 3413 | if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) { |
3414 | kfree(iter); | |
3415 | return -ENOMEM; | |
3416 | } | |
3417 | ||
3f2367ba MH |
3418 | iter->ops = ops; |
3419 | iter->flags = flag; | |
3420 | ||
33b7f99c | 3421 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 3422 | |
f45948e8 | 3423 | if (flag & FTRACE_ITER_NOTRACE) |
33b7f99c | 3424 | hash = ops->func_hash->notrace_hash; |
f45948e8 | 3425 | else |
33b7f99c | 3426 | hash = ops->func_hash->filter_hash; |
f45948e8 | 3427 | |
33dc9b12 | 3428 | if (file->f_mode & FMODE_WRITE) { |
ef2fbe16 NK |
3429 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; |
3430 | ||
3431 | if (file->f_flags & O_TRUNC) | |
3432 | iter->hash = alloc_ftrace_hash(size_bits); | |
3433 | else | |
3434 | iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash); | |
3435 | ||
33dc9b12 SR |
3436 | if (!iter->hash) { |
3437 | trace_parser_put(&iter->parser); | |
3438 | kfree(iter); | |
3f2367ba MH |
3439 | ret = -ENOMEM; |
3440 | goto out_unlock; | |
33dc9b12 SR |
3441 | } |
3442 | } | |
1cf41dd7 | 3443 | |
5072c59f SR |
3444 | if (file->f_mode & FMODE_READ) { |
3445 | iter->pg = ftrace_pages_start; | |
5072c59f SR |
3446 | |
3447 | ret = seq_open(file, &show_ftrace_seq_ops); | |
3448 | if (!ret) { | |
3449 | struct seq_file *m = file->private_data; | |
3450 | m->private = iter; | |
79fe249c | 3451 | } else { |
33dc9b12 SR |
3452 | /* Failed */ |
3453 | free_ftrace_hash(iter->hash); | |
79fe249c | 3454 | trace_parser_put(&iter->parser); |
5072c59f | 3455 | kfree(iter); |
79fe249c | 3456 | } |
5072c59f SR |
3457 | } else |
3458 | file->private_data = iter; | |
3f2367ba MH |
3459 | |
3460 | out_unlock: | |
33b7f99c | 3461 | mutex_unlock(&ops->func_hash->regex_lock); |
5072c59f SR |
3462 | |
3463 | return ret; | |
3464 | } | |
3465 | ||
41c52c0d SR |
3466 | static int |
3467 | ftrace_filter_open(struct inode *inode, struct file *file) | |
3468 | { | |
e3b3e2e8 SRRH |
3469 | struct ftrace_ops *ops = inode->i_private; |
3470 | ||
3471 | return ftrace_regex_open(ops, | |
69a3083c SR |
3472 | FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH, |
3473 | inode, file); | |
41c52c0d SR |
3474 | } |
3475 | ||
3476 | static int | |
3477 | ftrace_notrace_open(struct inode *inode, struct file *file) | |
3478 | { | |
e3b3e2e8 SRRH |
3479 | struct ftrace_ops *ops = inode->i_private; |
3480 | ||
3481 | return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE, | |
1cf41dd7 | 3482 | inode, file); |
41c52c0d SR |
3483 | } |
3484 | ||
3ba00929 DS |
3485 | /* Type for quick search ftrace basic regexes (globs) from filter_parse_regex */ |
3486 | struct ftrace_glob { | |
3487 | char *search; | |
3488 | unsigned len; | |
3489 | int type; | |
3490 | }; | |
3491 | ||
7132e2d6 TJB |
3492 | /* |
3493 | * If symbols in an architecture don't correspond exactly to the user-visible | |
3494 | * name of what they represent, it is possible to define this function to | |
3495 | * perform the necessary adjustments. | |
3496 | */ | |
3497 | char * __weak arch_ftrace_match_adjust(char *str, const char *search) | |
3498 | { | |
3499 | return str; | |
3500 | } | |
3501 | ||
3ba00929 | 3502 | static int ftrace_match(char *str, struct ftrace_glob *g) |
9f4801e3 | 3503 | { |
9f4801e3 | 3504 | int matched = 0; |
751e9983 | 3505 | int slen; |
9f4801e3 | 3506 | |
7132e2d6 TJB |
3507 | str = arch_ftrace_match_adjust(str, g->search); |
3508 | ||
3ba00929 | 3509 | switch (g->type) { |
9f4801e3 | 3510 | case MATCH_FULL: |
3ba00929 | 3511 | if (strcmp(str, g->search) == 0) |
9f4801e3 SR |
3512 | matched = 1; |
3513 | break; | |
3514 | case MATCH_FRONT_ONLY: | |
3ba00929 | 3515 | if (strncmp(str, g->search, g->len) == 0) |
9f4801e3 SR |
3516 | matched = 1; |
3517 | break; | |
3518 | case MATCH_MIDDLE_ONLY: | |
3ba00929 | 3519 | if (strstr(str, g->search)) |
9f4801e3 SR |
3520 | matched = 1; |
3521 | break; | |
3522 | case MATCH_END_ONLY: | |
751e9983 | 3523 | slen = strlen(str); |
3ba00929 DS |
3524 | if (slen >= g->len && |
3525 | memcmp(str + slen - g->len, g->search, g->len) == 0) | |
9f4801e3 SR |
3526 | matched = 1; |
3527 | break; | |
60f1d5e3 MH |
3528 | case MATCH_GLOB: |
3529 | if (glob_match(g->search, str)) | |
3530 | matched = 1; | |
3531 | break; | |
9f4801e3 SR |
3532 | } |
3533 | ||
3534 | return matched; | |
3535 | } | |
3536 | ||
b448c4e3 | 3537 | static int |
f0a3b154 | 3538 | enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter) |
996e87be | 3539 | { |
b448c4e3 | 3540 | struct ftrace_func_entry *entry; |
b448c4e3 SR |
3541 | int ret = 0; |
3542 | ||
1cf41dd7 | 3543 | entry = ftrace_lookup_ip(hash, rec->ip); |
f0a3b154 | 3544 | if (clear_filter) { |
1cf41dd7 SR |
3545 | /* Do nothing if it doesn't exist */ |
3546 | if (!entry) | |
3547 | return 0; | |
b448c4e3 | 3548 | |
33dc9b12 | 3549 | free_hash_entry(hash, entry); |
1cf41dd7 SR |
3550 | } else { |
3551 | /* Do nothing if it exists */ | |
3552 | if (entry) | |
3553 | return 0; | |
b448c4e3 | 3554 | |
1cf41dd7 | 3555 | ret = add_hash_entry(hash, rec->ip); |
b448c4e3 SR |
3556 | } |
3557 | return ret; | |
996e87be SR |
3558 | } |
3559 | ||
64e7c440 | 3560 | static int |
0b507e1e DS |
3561 | ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g, |
3562 | struct ftrace_glob *mod_g, int exclude_mod) | |
64e7c440 SR |
3563 | { |
3564 | char str[KSYM_SYMBOL_LEN]; | |
b9df92d2 SR |
3565 | char *modname; |
3566 | ||
3567 | kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); | |
3568 | ||
0b507e1e DS |
3569 | if (mod_g) { |
3570 | int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0; | |
3571 | ||
3572 | /* blank module name to match all modules */ | |
3573 | if (!mod_g->len) { | |
3574 | /* blank module globbing: modname xor exclude_mod */ | |
3575 | if ((!exclude_mod) != (!modname)) | |
3576 | goto func_match; | |
3577 | return 0; | |
3578 | } | |
3579 | ||
3580 | /* not matching the module */ | |
3581 | if (!modname || !mod_matches) { | |
3582 | if (exclude_mod) | |
3583 | goto func_match; | |
3584 | else | |
3585 | return 0; | |
3586 | } | |
3587 | ||
3588 | if (mod_matches && exclude_mod) | |
b9df92d2 SR |
3589 | return 0; |
3590 | ||
0b507e1e | 3591 | func_match: |
b9df92d2 | 3592 | /* blank search means to match all funcs in the mod */ |
3ba00929 | 3593 | if (!func_g->len) |
b9df92d2 SR |
3594 | return 1; |
3595 | } | |
64e7c440 | 3596 | |
3ba00929 | 3597 | return ftrace_match(str, func_g); |
64e7c440 SR |
3598 | } |
3599 | ||
1cf41dd7 | 3600 | static int |
3ba00929 | 3601 | match_records(struct ftrace_hash *hash, char *func, int len, char *mod) |
9f4801e3 | 3602 | { |
9f4801e3 SR |
3603 | struct ftrace_page *pg; |
3604 | struct dyn_ftrace *rec; | |
3ba00929 | 3605 | struct ftrace_glob func_g = { .type = MATCH_FULL }; |
0b507e1e DS |
3606 | struct ftrace_glob mod_g = { .type = MATCH_FULL }; |
3607 | struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL; | |
3608 | int exclude_mod = 0; | |
311d16da | 3609 | int found = 0; |
b448c4e3 | 3610 | int ret; |
f0a3b154 | 3611 | int clear_filter; |
9f4801e3 | 3612 | |
0b507e1e | 3613 | if (func) { |
3ba00929 DS |
3614 | func_g.type = filter_parse_regex(func, len, &func_g.search, |
3615 | &clear_filter); | |
3616 | func_g.len = strlen(func_g.search); | |
b9df92d2 | 3617 | } |
9f4801e3 | 3618 | |
0b507e1e DS |
3619 | if (mod) { |
3620 | mod_g.type = filter_parse_regex(mod, strlen(mod), | |
3621 | &mod_g.search, &exclude_mod); | |
3622 | mod_g.len = strlen(mod_g.search); | |
b9df92d2 | 3623 | } |
9f4801e3 | 3624 | |
52baf119 | 3625 | mutex_lock(&ftrace_lock); |
265c831c | 3626 | |
b9df92d2 SR |
3627 | if (unlikely(ftrace_disabled)) |
3628 | goto out_unlock; | |
9f4801e3 | 3629 | |
265c831c | 3630 | do_for_each_ftrace_rec(pg, rec) { |
546fece4 SRRH |
3631 | |
3632 | if (rec->flags & FTRACE_FL_DISABLED) | |
3633 | continue; | |
3634 | ||
0b507e1e | 3635 | if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) { |
f0a3b154 | 3636 | ret = enter_record(hash, rec, clear_filter); |
b448c4e3 SR |
3637 | if (ret < 0) { |
3638 | found = ret; | |
3639 | goto out_unlock; | |
3640 | } | |
311d16da | 3641 | found = 1; |
265c831c SR |
3642 | } |
3643 | } while_for_each_ftrace_rec(); | |
b9df92d2 | 3644 | out_unlock: |
52baf119 | 3645 | mutex_unlock(&ftrace_lock); |
311d16da LZ |
3646 | |
3647 | return found; | |
5072c59f SR |
3648 | } |
3649 | ||
64e7c440 | 3650 | static int |
1cf41dd7 | 3651 | ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) |
64e7c440 | 3652 | { |
f0a3b154 | 3653 | return match_records(hash, buff, len, NULL); |
64e7c440 SR |
3654 | } |
3655 | ||
64e7c440 | 3656 | |
f6180773 SR |
3657 | /* |
3658 | * We register the module command as a template to show others how | |
3659 | * to register the a command as well. | |
3660 | */ | |
3661 | ||
3662 | static int | |
43dd61c9 | 3663 | ftrace_mod_callback(struct ftrace_hash *hash, |
f0a3b154 | 3664 | char *func, char *cmd, char *module, int enable) |
f6180773 | 3665 | { |
5e3949f0 | 3666 | int ret; |
f6180773 SR |
3667 | |
3668 | /* | |
3669 | * cmd == 'mod' because we only registered this func | |
3670 | * for the 'mod' ftrace_func_command. | |
3671 | * But if you register one func with multiple commands, | |
3672 | * you can tell which command was used by the cmd | |
3673 | * parameter. | |
3674 | */ | |
f0a3b154 | 3675 | ret = match_records(hash, func, strlen(func), module); |
b448c4e3 | 3676 | if (!ret) |
5e3949f0 | 3677 | return -EINVAL; |
b448c4e3 SR |
3678 | if (ret < 0) |
3679 | return ret; | |
b448c4e3 | 3680 | return 0; |
f6180773 SR |
3681 | } |
3682 | ||
3683 | static struct ftrace_func_command ftrace_mod_cmd = { | |
3684 | .name = "mod", | |
3685 | .func = ftrace_mod_callback, | |
3686 | }; | |
3687 | ||
3688 | static int __init ftrace_mod_cmd_init(void) | |
3689 | { | |
3690 | return register_ftrace_command(&ftrace_mod_cmd); | |
3691 | } | |
6f415672 | 3692 | core_initcall(ftrace_mod_cmd_init); |
f6180773 | 3693 | |
2f5f6ad9 | 3694 | static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip, |
a1e2e31d | 3695 | struct ftrace_ops *op, struct pt_regs *pt_regs) |
59df055f | 3696 | { |
b6887d79 | 3697 | struct ftrace_func_probe *entry; |
59df055f | 3698 | struct hlist_head *hhd; |
59df055f | 3699 | unsigned long key; |
59df055f SR |
3700 | |
3701 | key = hash_long(ip, FTRACE_HASH_BITS); | |
3702 | ||
3703 | hhd = &ftrace_func_hash[key]; | |
3704 | ||
3705 | if (hlist_empty(hhd)) | |
3706 | return; | |
3707 | ||
3708 | /* | |
3709 | * Disable preemption for these calls to prevent a RCU grace | |
3710 | * period. This syncs the hash iteration and freeing of items | |
3711 | * on the hash. rcu_read_lock is too dangerous here. | |
3712 | */ | |
5168ae50 | 3713 | preempt_disable_notrace(); |
1bb539ca | 3714 | hlist_for_each_entry_rcu_notrace(entry, hhd, node) { |
59df055f SR |
3715 | if (entry->ip == ip) |
3716 | entry->ops->func(ip, parent_ip, &entry->data); | |
3717 | } | |
5168ae50 | 3718 | preempt_enable_notrace(); |
59df055f SR |
3719 | } |
3720 | ||
b6887d79 | 3721 | static struct ftrace_ops trace_probe_ops __read_mostly = |
59df055f | 3722 | { |
fb9fb015 | 3723 | .func = function_trace_probe_call, |
f04f24fb | 3724 | .flags = FTRACE_OPS_FL_INITIALIZED, |
33b7f99c | 3725 | INIT_OPS_HASH(trace_probe_ops) |
59df055f SR |
3726 | }; |
3727 | ||
b6887d79 | 3728 | static int ftrace_probe_registered; |
59df055f | 3729 | |
7485058e | 3730 | static void __enable_ftrace_function_probe(struct ftrace_ops_hash *old_hash) |
59df055f | 3731 | { |
b848914c | 3732 | int ret; |
59df055f SR |
3733 | int i; |
3734 | ||
19dd603e SRRH |
3735 | if (ftrace_probe_registered) { |
3736 | /* still need to update the function call sites */ | |
3737 | if (ftrace_enabled) | |
8252ecf3 SRRH |
3738 | ftrace_run_modify_code(&trace_probe_ops, FTRACE_UPDATE_CALLS, |
3739 | old_hash); | |
59df055f | 3740 | return; |
19dd603e | 3741 | } |
59df055f SR |
3742 | |
3743 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3744 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3745 | if (hhd->first) | |
3746 | break; | |
3747 | } | |
3748 | /* Nothing registered? */ | |
3749 | if (i == FTRACE_FUNC_HASHSIZE) | |
3750 | return; | |
3751 | ||
8a56d776 | 3752 | ret = ftrace_startup(&trace_probe_ops, 0); |
b848914c | 3753 | |
b6887d79 | 3754 | ftrace_probe_registered = 1; |
59df055f SR |
3755 | } |
3756 | ||
b6887d79 | 3757 | static void __disable_ftrace_function_probe(void) |
59df055f SR |
3758 | { |
3759 | int i; | |
3760 | ||
b6887d79 | 3761 | if (!ftrace_probe_registered) |
59df055f SR |
3762 | return; |
3763 | ||
3764 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { | |
3765 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3766 | if (hhd->first) | |
3767 | return; | |
3768 | } | |
3769 | ||
3770 | /* no more funcs left */ | |
8a56d776 | 3771 | ftrace_shutdown(&trace_probe_ops, 0); |
b848914c | 3772 | |
b6887d79 | 3773 | ftrace_probe_registered = 0; |
59df055f SR |
3774 | } |
3775 | ||
3776 | ||
7818b388 | 3777 | static void ftrace_free_entry(struct ftrace_func_probe *entry) |
59df055f | 3778 | { |
59df055f | 3779 | if (entry->ops->free) |
e67efb93 | 3780 | entry->ops->free(entry->ops, entry->ip, &entry->data); |
59df055f SR |
3781 | kfree(entry); |
3782 | } | |
3783 | ||
59df055f | 3784 | int |
b6887d79 | 3785 | register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3786 | void *data) |
3787 | { | |
7485058e | 3788 | struct ftrace_ops_hash old_hash_ops; |
b6887d79 | 3789 | struct ftrace_func_probe *entry; |
3ba00929 | 3790 | struct ftrace_glob func_g; |
33b7f99c | 3791 | struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash; |
3296fc4e | 3792 | struct ftrace_hash *old_hash = *orig_hash; |
e1df4cb6 | 3793 | struct ftrace_hash *hash; |
59df055f SR |
3794 | struct ftrace_page *pg; |
3795 | struct dyn_ftrace *rec; | |
3ba00929 | 3796 | int not; |
6a24a244 | 3797 | unsigned long key; |
59df055f | 3798 | int count = 0; |
e1df4cb6 | 3799 | int ret; |
59df055f | 3800 | |
3ba00929 DS |
3801 | func_g.type = filter_parse_regex(glob, strlen(glob), |
3802 | &func_g.search, ¬); | |
3803 | func_g.len = strlen(func_g.search); | |
59df055f | 3804 | |
b6887d79 | 3805 | /* we do not support '!' for function probes */ |
59df055f SR |
3806 | if (WARN_ON(not)) |
3807 | return -EINVAL; | |
3808 | ||
33b7f99c | 3809 | mutex_lock(&trace_probe_ops.func_hash->regex_lock); |
59df055f | 3810 | |
7485058e SRRH |
3811 | old_hash_ops.filter_hash = old_hash; |
3812 | /* Probes only have filters */ | |
3813 | old_hash_ops.notrace_hash = NULL; | |
3814 | ||
3296fc4e | 3815 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); |
e1df4cb6 SRRH |
3816 | if (!hash) { |
3817 | count = -ENOMEM; | |
5ae0bf59 | 3818 | goto out; |
e1df4cb6 SRRH |
3819 | } |
3820 | ||
3821 | if (unlikely(ftrace_disabled)) { | |
3822 | count = -ENODEV; | |
5ae0bf59 | 3823 | goto out; |
e1df4cb6 | 3824 | } |
59df055f | 3825 | |
5ae0bf59 SRRH |
3826 | mutex_lock(&ftrace_lock); |
3827 | ||
45a4a237 | 3828 | do_for_each_ftrace_rec(pg, rec) { |
59df055f | 3829 | |
546fece4 SRRH |
3830 | if (rec->flags & FTRACE_FL_DISABLED) |
3831 | continue; | |
3832 | ||
0b507e1e | 3833 | if (!ftrace_match_record(rec, &func_g, NULL, 0)) |
59df055f SR |
3834 | continue; |
3835 | ||
3836 | entry = kmalloc(sizeof(*entry), GFP_KERNEL); | |
3837 | if (!entry) { | |
b6887d79 | 3838 | /* If we did not process any, then return error */ |
59df055f SR |
3839 | if (!count) |
3840 | count = -ENOMEM; | |
3841 | goto out_unlock; | |
3842 | } | |
3843 | ||
3844 | count++; | |
3845 | ||
3846 | entry->data = data; | |
3847 | ||
3848 | /* | |
3849 | * The caller might want to do something special | |
3850 | * for each function we find. We call the callback | |
3851 | * to give the caller an opportunity to do so. | |
3852 | */ | |
e67efb93 SRRH |
3853 | if (ops->init) { |
3854 | if (ops->init(ops, rec->ip, &entry->data) < 0) { | |
59df055f SR |
3855 | /* caller does not like this func */ |
3856 | kfree(entry); | |
3857 | continue; | |
3858 | } | |
3859 | } | |
3860 | ||
e1df4cb6 SRRH |
3861 | ret = enter_record(hash, rec, 0); |
3862 | if (ret < 0) { | |
3863 | kfree(entry); | |
3864 | count = ret; | |
3865 | goto out_unlock; | |
3866 | } | |
3867 | ||
59df055f SR |
3868 | entry->ops = ops; |
3869 | entry->ip = rec->ip; | |
3870 | ||
3871 | key = hash_long(entry->ip, FTRACE_HASH_BITS); | |
3872 | hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]); | |
3873 | ||
3874 | } while_for_each_ftrace_rec(); | |
e1df4cb6 SRRH |
3875 | |
3876 | ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); | |
8252ecf3 | 3877 | |
7485058e | 3878 | __enable_ftrace_function_probe(&old_hash_ops); |
8252ecf3 | 3879 | |
3296fc4e SRRH |
3880 | if (!ret) |
3881 | free_ftrace_hash_rcu(old_hash); | |
3882 | else | |
e1df4cb6 SRRH |
3883 | count = ret; |
3884 | ||
59df055f | 3885 | out_unlock: |
5ae0bf59 SRRH |
3886 | mutex_unlock(&ftrace_lock); |
3887 | out: | |
33b7f99c | 3888 | mutex_unlock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 | 3889 | free_ftrace_hash(hash); |
59df055f SR |
3890 | |
3891 | return count; | |
3892 | } | |
3893 | ||
3894 | enum { | |
b6887d79 SR |
3895 | PROBE_TEST_FUNC = 1, |
3896 | PROBE_TEST_DATA = 2 | |
59df055f SR |
3897 | }; |
3898 | ||
3899 | static void | |
b6887d79 | 3900 | __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3901 | void *data, int flags) |
3902 | { | |
e1df4cb6 | 3903 | struct ftrace_func_entry *rec_entry; |
b6887d79 | 3904 | struct ftrace_func_probe *entry; |
7818b388 | 3905 | struct ftrace_func_probe *p; |
3ba00929 | 3906 | struct ftrace_glob func_g; |
33b7f99c | 3907 | struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash; |
3296fc4e | 3908 | struct ftrace_hash *old_hash = *orig_hash; |
7818b388 | 3909 | struct list_head free_list; |
e1df4cb6 | 3910 | struct ftrace_hash *hash; |
b67bfe0d | 3911 | struct hlist_node *tmp; |
59df055f | 3912 | char str[KSYM_SYMBOL_LEN]; |
3ba00929 | 3913 | int i, ret; |
59df055f | 3914 | |
b36461da | 3915 | if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) |
3ba00929 | 3916 | func_g.search = NULL; |
b36461da | 3917 | else if (glob) { |
59df055f SR |
3918 | int not; |
3919 | ||
3ba00929 DS |
3920 | func_g.type = filter_parse_regex(glob, strlen(glob), |
3921 | &func_g.search, ¬); | |
3922 | func_g.len = strlen(func_g.search); | |
3923 | func_g.search = glob; | |
59df055f | 3924 | |
b6887d79 | 3925 | /* we do not support '!' for function probes */ |
59df055f SR |
3926 | if (WARN_ON(not)) |
3927 | return; | |
3928 | } | |
3929 | ||
33b7f99c | 3930 | mutex_lock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 SRRH |
3931 | |
3932 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
3933 | if (!hash) | |
3934 | /* Hmm, should report this somehow */ | |
3935 | goto out_unlock; | |
3936 | ||
7818b388 SRRH |
3937 | INIT_LIST_HEAD(&free_list); |
3938 | ||
59df055f SR |
3939 | for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) { |
3940 | struct hlist_head *hhd = &ftrace_func_hash[i]; | |
3941 | ||
b67bfe0d | 3942 | hlist_for_each_entry_safe(entry, tmp, hhd, node) { |
59df055f SR |
3943 | |
3944 | /* break up if statements for readability */ | |
b6887d79 | 3945 | if ((flags & PROBE_TEST_FUNC) && entry->ops != ops) |
59df055f SR |
3946 | continue; |
3947 | ||
b6887d79 | 3948 | if ((flags & PROBE_TEST_DATA) && entry->data != data) |
59df055f SR |
3949 | continue; |
3950 | ||
3951 | /* do this last, since it is the most expensive */ | |
3ba00929 | 3952 | if (func_g.search) { |
59df055f SR |
3953 | kallsyms_lookup(entry->ip, NULL, NULL, |
3954 | NULL, str); | |
3ba00929 | 3955 | if (!ftrace_match(str, &func_g)) |
59df055f SR |
3956 | continue; |
3957 | } | |
3958 | ||
e1df4cb6 SRRH |
3959 | rec_entry = ftrace_lookup_ip(hash, entry->ip); |
3960 | /* It is possible more than one entry had this ip */ | |
3961 | if (rec_entry) | |
3962 | free_hash_entry(hash, rec_entry); | |
3963 | ||
740466bc | 3964 | hlist_del_rcu(&entry->node); |
7818b388 | 3965 | list_add(&entry->free_list, &free_list); |
59df055f SR |
3966 | } |
3967 | } | |
3f2367ba | 3968 | mutex_lock(&ftrace_lock); |
b6887d79 | 3969 | __disable_ftrace_function_probe(); |
e1df4cb6 SRRH |
3970 | /* |
3971 | * Remove after the disable is called. Otherwise, if the last | |
3972 | * probe is removed, a null hash means *all enabled*. | |
3973 | */ | |
3296fc4e | 3974 | ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash); |
7818b388 | 3975 | synchronize_sched(); |
3296fc4e SRRH |
3976 | if (!ret) |
3977 | free_ftrace_hash_rcu(old_hash); | |
3978 | ||
7818b388 SRRH |
3979 | list_for_each_entry_safe(entry, p, &free_list, free_list) { |
3980 | list_del(&entry->free_list); | |
3981 | ftrace_free_entry(entry); | |
3982 | } | |
3f2367ba | 3983 | mutex_unlock(&ftrace_lock); |
3ba00929 | 3984 | |
e1df4cb6 | 3985 | out_unlock: |
33b7f99c | 3986 | mutex_unlock(&trace_probe_ops.func_hash->regex_lock); |
e1df4cb6 | 3987 | free_ftrace_hash(hash); |
59df055f SR |
3988 | } |
3989 | ||
3990 | void | |
b6887d79 | 3991 | unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, |
59df055f SR |
3992 | void *data) |
3993 | { | |
b6887d79 SR |
3994 | __unregister_ftrace_function_probe(glob, ops, data, |
3995 | PROBE_TEST_FUNC | PROBE_TEST_DATA); | |
59df055f SR |
3996 | } |
3997 | ||
3998 | void | |
b6887d79 | 3999 | unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops) |
59df055f | 4000 | { |
b6887d79 | 4001 | __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC); |
59df055f SR |
4002 | } |
4003 | ||
b6887d79 | 4004 | void unregister_ftrace_function_probe_all(char *glob) |
59df055f | 4005 | { |
b6887d79 | 4006 | __unregister_ftrace_function_probe(glob, NULL, NULL, 0); |
59df055f SR |
4007 | } |
4008 | ||
f6180773 SR |
4009 | static LIST_HEAD(ftrace_commands); |
4010 | static DEFINE_MUTEX(ftrace_cmd_mutex); | |
4011 | ||
38de93ab TZ |
4012 | /* |
4013 | * Currently we only register ftrace commands from __init, so mark this | |
4014 | * __init too. | |
4015 | */ | |
4016 | __init int register_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4017 | { |
4018 | struct ftrace_func_command *p; | |
4019 | int ret = 0; | |
4020 | ||
4021 | mutex_lock(&ftrace_cmd_mutex); | |
4022 | list_for_each_entry(p, &ftrace_commands, list) { | |
4023 | if (strcmp(cmd->name, p->name) == 0) { | |
4024 | ret = -EBUSY; | |
4025 | goto out_unlock; | |
4026 | } | |
4027 | } | |
4028 | list_add(&cmd->list, &ftrace_commands); | |
4029 | out_unlock: | |
4030 | mutex_unlock(&ftrace_cmd_mutex); | |
4031 | ||
4032 | return ret; | |
4033 | } | |
4034 | ||
38de93ab TZ |
4035 | /* |
4036 | * Currently we only unregister ftrace commands from __init, so mark | |
4037 | * this __init too. | |
4038 | */ | |
4039 | __init int unregister_ftrace_command(struct ftrace_func_command *cmd) | |
f6180773 SR |
4040 | { |
4041 | struct ftrace_func_command *p, *n; | |
4042 | int ret = -ENODEV; | |
4043 | ||
4044 | mutex_lock(&ftrace_cmd_mutex); | |
4045 | list_for_each_entry_safe(p, n, &ftrace_commands, list) { | |
4046 | if (strcmp(cmd->name, p->name) == 0) { | |
4047 | ret = 0; | |
4048 | list_del_init(&p->list); | |
4049 | goto out_unlock; | |
4050 | } | |
4051 | } | |
4052 | out_unlock: | |
4053 | mutex_unlock(&ftrace_cmd_mutex); | |
4054 | ||
4055 | return ret; | |
4056 | } | |
4057 | ||
33dc9b12 SR |
4058 | static int ftrace_process_regex(struct ftrace_hash *hash, |
4059 | char *buff, int len, int enable) | |
64e7c440 | 4060 | { |
f6180773 | 4061 | char *func, *command, *next = buff; |
6a24a244 | 4062 | struct ftrace_func_command *p; |
0aff1c0c | 4063 | int ret = -EINVAL; |
64e7c440 SR |
4064 | |
4065 | func = strsep(&next, ":"); | |
4066 | ||
4067 | if (!next) { | |
1cf41dd7 | 4068 | ret = ftrace_match_records(hash, func, len); |
b448c4e3 SR |
4069 | if (!ret) |
4070 | ret = -EINVAL; | |
4071 | if (ret < 0) | |
4072 | return ret; | |
4073 | return 0; | |
64e7c440 SR |
4074 | } |
4075 | ||
f6180773 | 4076 | /* command found */ |
64e7c440 SR |
4077 | |
4078 | command = strsep(&next, ":"); | |
4079 | ||
f6180773 SR |
4080 | mutex_lock(&ftrace_cmd_mutex); |
4081 | list_for_each_entry(p, &ftrace_commands, list) { | |
4082 | if (strcmp(p->name, command) == 0) { | |
43dd61c9 | 4083 | ret = p->func(hash, func, command, next, enable); |
f6180773 SR |
4084 | goto out_unlock; |
4085 | } | |
64e7c440 | 4086 | } |
f6180773 SR |
4087 | out_unlock: |
4088 | mutex_unlock(&ftrace_cmd_mutex); | |
64e7c440 | 4089 | |
f6180773 | 4090 | return ret; |
64e7c440 SR |
4091 | } |
4092 | ||
e309b41d | 4093 | static ssize_t |
41c52c0d SR |
4094 | ftrace_regex_write(struct file *file, const char __user *ubuf, |
4095 | size_t cnt, loff_t *ppos, int enable) | |
5072c59f SR |
4096 | { |
4097 | struct ftrace_iterator *iter; | |
689fd8b6 | 4098 | struct trace_parser *parser; |
4099 | ssize_t ret, read; | |
5072c59f | 4100 | |
4ba7978e | 4101 | if (!cnt) |
5072c59f SR |
4102 | return 0; |
4103 | ||
5072c59f SR |
4104 | if (file->f_mode & FMODE_READ) { |
4105 | struct seq_file *m = file->private_data; | |
4106 | iter = m->private; | |
4107 | } else | |
4108 | iter = file->private_data; | |
4109 | ||
f04f24fb | 4110 | if (unlikely(ftrace_disabled)) |
3f2367ba MH |
4111 | return -ENODEV; |
4112 | ||
4113 | /* iter->hash is a local copy, so we don't need regex_lock */ | |
f04f24fb | 4114 | |
689fd8b6 | 4115 | parser = &iter->parser; |
4116 | read = trace_get_user(parser, ubuf, cnt, ppos); | |
5072c59f | 4117 | |
4ba7978e | 4118 | if (read >= 0 && trace_parser_loaded(parser) && |
689fd8b6 | 4119 | !trace_parser_cont(parser)) { |
33dc9b12 | 4120 | ret = ftrace_process_regex(iter->hash, parser->buffer, |
689fd8b6 | 4121 | parser->idx, enable); |
313254a9 | 4122 | trace_parser_clear(parser); |
7c088b51 | 4123 | if (ret < 0) |
3f2367ba | 4124 | goto out; |
eda1e328 | 4125 | } |
5072c59f | 4126 | |
5072c59f | 4127 | ret = read; |
3f2367ba | 4128 | out: |
5072c59f SR |
4129 | return ret; |
4130 | } | |
4131 | ||
fc13cb0c | 4132 | ssize_t |
41c52c0d SR |
4133 | ftrace_filter_write(struct file *file, const char __user *ubuf, |
4134 | size_t cnt, loff_t *ppos) | |
4135 | { | |
4136 | return ftrace_regex_write(file, ubuf, cnt, ppos, 1); | |
4137 | } | |
4138 | ||
fc13cb0c | 4139 | ssize_t |
41c52c0d SR |
4140 | ftrace_notrace_write(struct file *file, const char __user *ubuf, |
4141 | size_t cnt, loff_t *ppos) | |
4142 | { | |
4143 | return ftrace_regex_write(file, ubuf, cnt, ppos, 0); | |
4144 | } | |
4145 | ||
33dc9b12 | 4146 | static int |
647664ea MH |
4147 | ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) |
4148 | { | |
4149 | struct ftrace_func_entry *entry; | |
4150 | ||
4151 | if (!ftrace_location(ip)) | |
4152 | return -EINVAL; | |
4153 | ||
4154 | if (remove) { | |
4155 | entry = ftrace_lookup_ip(hash, ip); | |
4156 | if (!entry) | |
4157 | return -ENOENT; | |
4158 | free_hash_entry(hash, entry); | |
4159 | return 0; | |
4160 | } | |
4161 | ||
4162 | return add_hash_entry(hash, ip); | |
4163 | } | |
4164 | ||
8252ecf3 | 4165 | static void ftrace_ops_update_code(struct ftrace_ops *ops, |
7485058e | 4166 | struct ftrace_ops_hash *old_hash) |
1c80c432 | 4167 | { |
8f86f837 SRRH |
4168 | struct ftrace_ops *op; |
4169 | ||
4170 | if (!ftrace_enabled) | |
4171 | return; | |
4172 | ||
4173 | if (ops->flags & FTRACE_OPS_FL_ENABLED) { | |
8252ecf3 | 4174 | ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); |
8f86f837 SRRH |
4175 | return; |
4176 | } | |
4177 | ||
4178 | /* | |
4179 | * If this is the shared global_ops filter, then we need to | |
4180 | * check if there is another ops that shares it, is enabled. | |
4181 | * If so, we still need to run the modify code. | |
4182 | */ | |
4183 | if (ops->func_hash != &global_ops.local_hash) | |
4184 | return; | |
4185 | ||
4186 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
4187 | if (op->func_hash == &global_ops.local_hash && | |
4188 | op->flags & FTRACE_OPS_FL_ENABLED) { | |
4189 | ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); | |
4190 | /* Only need to do this once */ | |
4191 | return; | |
4192 | } | |
4193 | } while_for_each_ftrace_op(op); | |
1c80c432 SRRH |
4194 | } |
4195 | ||
647664ea MH |
4196 | static int |
4197 | ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4198 | unsigned long ip, int remove, int reset, int enable) | |
41c52c0d | 4199 | { |
33dc9b12 | 4200 | struct ftrace_hash **orig_hash; |
7485058e | 4201 | struct ftrace_ops_hash old_hash_ops; |
3296fc4e | 4202 | struct ftrace_hash *old_hash; |
f45948e8 | 4203 | struct ftrace_hash *hash; |
33dc9b12 | 4204 | int ret; |
f45948e8 | 4205 | |
41c52c0d | 4206 | if (unlikely(ftrace_disabled)) |
33dc9b12 | 4207 | return -ENODEV; |
41c52c0d | 4208 | |
33b7f99c | 4209 | mutex_lock(&ops->func_hash->regex_lock); |
3f2367ba | 4210 | |
f45948e8 | 4211 | if (enable) |
33b7f99c | 4212 | orig_hash = &ops->func_hash->filter_hash; |
f45948e8 | 4213 | else |
33b7f99c | 4214 | orig_hash = &ops->func_hash->notrace_hash; |
33dc9b12 | 4215 | |
b972cc58 WN |
4216 | if (reset) |
4217 | hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS); | |
4218 | else | |
4219 | hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash); | |
4220 | ||
3f2367ba MH |
4221 | if (!hash) { |
4222 | ret = -ENOMEM; | |
4223 | goto out_regex_unlock; | |
4224 | } | |
f45948e8 | 4225 | |
ac483c44 JO |
4226 | if (buf && !ftrace_match_records(hash, buf, len)) { |
4227 | ret = -EINVAL; | |
4228 | goto out_regex_unlock; | |
4229 | } | |
647664ea MH |
4230 | if (ip) { |
4231 | ret = ftrace_match_addr(hash, ip, remove); | |
4232 | if (ret < 0) | |
4233 | goto out_regex_unlock; | |
4234 | } | |
33dc9b12 SR |
4235 | |
4236 | mutex_lock(&ftrace_lock); | |
3296fc4e | 4237 | old_hash = *orig_hash; |
7485058e SRRH |
4238 | old_hash_ops.filter_hash = ops->func_hash->filter_hash; |
4239 | old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; | |
41fb61c2 | 4240 | ret = ftrace_hash_move(ops, enable, orig_hash, hash); |
3296fc4e | 4241 | if (!ret) { |
7485058e | 4242 | ftrace_ops_update_code(ops, &old_hash_ops); |
3296fc4e SRRH |
4243 | free_ftrace_hash_rcu(old_hash); |
4244 | } | |
33dc9b12 SR |
4245 | mutex_unlock(&ftrace_lock); |
4246 | ||
ac483c44 | 4247 | out_regex_unlock: |
33b7f99c | 4248 | mutex_unlock(&ops->func_hash->regex_lock); |
33dc9b12 SR |
4249 | |
4250 | free_ftrace_hash(hash); | |
4251 | return ret; | |
41c52c0d SR |
4252 | } |
4253 | ||
647664ea MH |
4254 | static int |
4255 | ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove, | |
4256 | int reset, int enable) | |
4257 | { | |
4258 | return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable); | |
4259 | } | |
4260 | ||
4261 | /** | |
4262 | * ftrace_set_filter_ip - set a function to filter on in ftrace by address | |
4263 | * @ops - the ops to set the filter with | |
4264 | * @ip - the address to add to or remove from the filter. | |
4265 | * @remove - non zero to remove the ip from the filter | |
4266 | * @reset - non zero to reset all filters before applying this filter. | |
4267 | * | |
4268 | * Filters denote which functions should be enabled when tracing is enabled | |
4269 | * If @ip is NULL, it failes to update filter. | |
4270 | */ | |
4271 | int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, | |
4272 | int remove, int reset) | |
4273 | { | |
f04f24fb | 4274 | ftrace_ops_init(ops); |
647664ea MH |
4275 | return ftrace_set_addr(ops, ip, remove, reset, 1); |
4276 | } | |
4277 | EXPORT_SYMBOL_GPL(ftrace_set_filter_ip); | |
4278 | ||
d032ae89 JF |
4279 | /** |
4280 | * ftrace_ops_set_global_filter - setup ops to use global filters | |
4281 | * @ops - the ops which will use the global filters | |
4282 | * | |
4283 | * ftrace users who need global function trace filtering should call this. | |
4284 | * It can set the global filter only if ops were not initialized before. | |
4285 | */ | |
4286 | void ftrace_ops_set_global_filter(struct ftrace_ops *ops) | |
4287 | { | |
4288 | if (ops->flags & FTRACE_OPS_FL_INITIALIZED) | |
4289 | return; | |
4290 | ||
4291 | ftrace_ops_init(ops); | |
4292 | ops->func_hash = &global_ops.local_hash; | |
4293 | } | |
4294 | EXPORT_SYMBOL_GPL(ftrace_ops_set_global_filter); | |
4295 | ||
647664ea MH |
4296 | static int |
4297 | ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, | |
4298 | int reset, int enable) | |
4299 | { | |
4300 | return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable); | |
4301 | } | |
4302 | ||
77a2b37d SR |
4303 | /** |
4304 | * ftrace_set_filter - set a function to filter on in ftrace | |
936e074b SR |
4305 | * @ops - the ops to set the filter with |
4306 | * @buf - the string that holds the function filter text. | |
4307 | * @len - the length of the string. | |
4308 | * @reset - non zero to reset all filters before applying this filter. | |
4309 | * | |
4310 | * Filters denote which functions should be enabled when tracing is enabled. | |
4311 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4312 | */ | |
ac483c44 | 4313 | int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4314 | int len, int reset) |
4315 | { | |
f04f24fb | 4316 | ftrace_ops_init(ops); |
ac483c44 | 4317 | return ftrace_set_regex(ops, buf, len, reset, 1); |
936e074b SR |
4318 | } |
4319 | EXPORT_SYMBOL_GPL(ftrace_set_filter); | |
4320 | ||
4321 | /** | |
4322 | * ftrace_set_notrace - set a function to not trace in ftrace | |
4323 | * @ops - the ops to set the notrace filter with | |
4324 | * @buf - the string that holds the function notrace text. | |
4325 | * @len - the length of the string. | |
4326 | * @reset - non zero to reset all filters before applying this filter. | |
4327 | * | |
4328 | * Notrace Filters denote which functions should not be enabled when tracing | |
4329 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4330 | * for tracing. | |
4331 | */ | |
ac483c44 | 4332 | int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, |
936e074b SR |
4333 | int len, int reset) |
4334 | { | |
f04f24fb | 4335 | ftrace_ops_init(ops); |
ac483c44 | 4336 | return ftrace_set_regex(ops, buf, len, reset, 0); |
936e074b SR |
4337 | } |
4338 | EXPORT_SYMBOL_GPL(ftrace_set_notrace); | |
4339 | /** | |
8d1b065d | 4340 | * ftrace_set_global_filter - set a function to filter on with global tracers |
77a2b37d SR |
4341 | * @buf - the string that holds the function filter text. |
4342 | * @len - the length of the string. | |
4343 | * @reset - non zero to reset all filters before applying this filter. | |
4344 | * | |
4345 | * Filters denote which functions should be enabled when tracing is enabled. | |
4346 | * If @buf is NULL and reset is set, all functions will be enabled for tracing. | |
4347 | */ | |
936e074b | 4348 | void ftrace_set_global_filter(unsigned char *buf, int len, int reset) |
77a2b37d | 4349 | { |
f45948e8 | 4350 | ftrace_set_regex(&global_ops, buf, len, reset, 1); |
41c52c0d | 4351 | } |
936e074b | 4352 | EXPORT_SYMBOL_GPL(ftrace_set_global_filter); |
4eebcc81 | 4353 | |
41c52c0d | 4354 | /** |
8d1b065d | 4355 | * ftrace_set_global_notrace - set a function to not trace with global tracers |
41c52c0d SR |
4356 | * @buf - the string that holds the function notrace text. |
4357 | * @len - the length of the string. | |
4358 | * @reset - non zero to reset all filters before applying this filter. | |
4359 | * | |
4360 | * Notrace Filters denote which functions should not be enabled when tracing | |
4361 | * is enabled. If @buf is NULL and reset is set, all functions will be enabled | |
4362 | * for tracing. | |
4363 | */ | |
936e074b | 4364 | void ftrace_set_global_notrace(unsigned char *buf, int len, int reset) |
41c52c0d | 4365 | { |
f45948e8 | 4366 | ftrace_set_regex(&global_ops, buf, len, reset, 0); |
77a2b37d | 4367 | } |
936e074b | 4368 | EXPORT_SYMBOL_GPL(ftrace_set_global_notrace); |
77a2b37d | 4369 | |
2af15d6a SR |
4370 | /* |
4371 | * command line interface to allow users to set filters on boot up. | |
4372 | */ | |
4373 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | |
4374 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | |
4375 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | |
4376 | ||
f1ed7c74 SRRH |
4377 | /* Used by function selftest to not test if filter is set */ |
4378 | bool ftrace_filter_param __initdata; | |
4379 | ||
2af15d6a SR |
4380 | static int __init set_ftrace_notrace(char *str) |
4381 | { | |
f1ed7c74 | 4382 | ftrace_filter_param = true; |
75761cc1 | 4383 | strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4384 | return 1; |
4385 | } | |
4386 | __setup("ftrace_notrace=", set_ftrace_notrace); | |
4387 | ||
4388 | static int __init set_ftrace_filter(char *str) | |
4389 | { | |
f1ed7c74 | 4390 | ftrace_filter_param = true; |
75761cc1 | 4391 | strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); |
2af15d6a SR |
4392 | return 1; |
4393 | } | |
4394 | __setup("ftrace_filter=", set_ftrace_filter); | |
4395 | ||
369bc18f | 4396 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
f6060f46 | 4397 | static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; |
0d7d9a16 | 4398 | static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata; |
b9b0c831 | 4399 | static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); |
801c29fd | 4400 | |
f3bea491 SRRH |
4401 | static unsigned long save_global_trampoline; |
4402 | static unsigned long save_global_flags; | |
4403 | ||
369bc18f SA |
4404 | static int __init set_graph_function(char *str) |
4405 | { | |
06f43d66 | 4406 | strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE); |
369bc18f SA |
4407 | return 1; |
4408 | } | |
4409 | __setup("ftrace_graph_filter=", set_graph_function); | |
4410 | ||
0d7d9a16 NK |
4411 | static int __init set_graph_notrace_function(char *str) |
4412 | { | |
4413 | strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE); | |
4414 | return 1; | |
4415 | } | |
4416 | __setup("ftrace_graph_notrace=", set_graph_notrace_function); | |
4417 | ||
4418 | static void __init set_ftrace_early_graph(char *buf, int enable) | |
369bc18f SA |
4419 | { |
4420 | int ret; | |
4421 | char *func; | |
b9b0c831 | 4422 | struct ftrace_hash *hash; |
0d7d9a16 | 4423 | |
b9b0c831 NK |
4424 | if (enable) |
4425 | hash = ftrace_graph_hash; | |
4426 | else | |
4427 | hash = ftrace_graph_notrace_hash; | |
369bc18f SA |
4428 | |
4429 | while (buf) { | |
4430 | func = strsep(&buf, ","); | |
4431 | /* we allow only one expression at a time */ | |
b9b0c831 | 4432 | ret = ftrace_graph_set_hash(hash, func); |
369bc18f SA |
4433 | if (ret) |
4434 | printk(KERN_DEBUG "ftrace: function %s not " | |
4435 | "traceable\n", func); | |
4436 | } | |
4437 | } | |
4438 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
4439 | ||
2a85a37f SR |
4440 | void __init |
4441 | ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) | |
2af15d6a SR |
4442 | { |
4443 | char *func; | |
4444 | ||
f04f24fb MH |
4445 | ftrace_ops_init(ops); |
4446 | ||
2af15d6a SR |
4447 | while (buf) { |
4448 | func = strsep(&buf, ","); | |
f45948e8 | 4449 | ftrace_set_regex(ops, func, strlen(func), 0, enable); |
2af15d6a SR |
4450 | } |
4451 | } | |
4452 | ||
4453 | static void __init set_ftrace_early_filters(void) | |
4454 | { | |
4455 | if (ftrace_filter_buf[0]) | |
2a85a37f | 4456 | ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1); |
2af15d6a | 4457 | if (ftrace_notrace_buf[0]) |
2a85a37f | 4458 | ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0); |
369bc18f SA |
4459 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
4460 | if (ftrace_graph_buf[0]) | |
0d7d9a16 NK |
4461 | set_ftrace_early_graph(ftrace_graph_buf, 1); |
4462 | if (ftrace_graph_notrace_buf[0]) | |
4463 | set_ftrace_early_graph(ftrace_graph_notrace_buf, 0); | |
369bc18f | 4464 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
2af15d6a SR |
4465 | } |
4466 | ||
fc13cb0c | 4467 | int ftrace_regex_release(struct inode *inode, struct file *file) |
5072c59f SR |
4468 | { |
4469 | struct seq_file *m = (struct seq_file *)file->private_data; | |
7485058e | 4470 | struct ftrace_ops_hash old_hash_ops; |
5072c59f | 4471 | struct ftrace_iterator *iter; |
33dc9b12 | 4472 | struct ftrace_hash **orig_hash; |
3296fc4e | 4473 | struct ftrace_hash *old_hash; |
689fd8b6 | 4474 | struct trace_parser *parser; |
ed926f9b | 4475 | int filter_hash; |
33dc9b12 | 4476 | int ret; |
5072c59f | 4477 | |
5072c59f SR |
4478 | if (file->f_mode & FMODE_READ) { |
4479 | iter = m->private; | |
5072c59f SR |
4480 | seq_release(inode, file); |
4481 | } else | |
4482 | iter = file->private_data; | |
4483 | ||
689fd8b6 | 4484 | parser = &iter->parser; |
4485 | if (trace_parser_loaded(parser)) { | |
4486 | parser->buffer[parser->idx] = 0; | |
1cf41dd7 | 4487 | ftrace_match_records(iter->hash, parser->buffer, parser->idx); |
5072c59f SR |
4488 | } |
4489 | ||
689fd8b6 | 4490 | trace_parser_put(parser); |
689fd8b6 | 4491 | |
33b7f99c | 4492 | mutex_lock(&iter->ops->func_hash->regex_lock); |
3f2367ba | 4493 | |
058e297d | 4494 | if (file->f_mode & FMODE_WRITE) { |
ed926f9b SR |
4495 | filter_hash = !!(iter->flags & FTRACE_ITER_FILTER); |
4496 | ||
4497 | if (filter_hash) | |
33b7f99c | 4498 | orig_hash = &iter->ops->func_hash->filter_hash; |
ed926f9b | 4499 | else |
33b7f99c | 4500 | orig_hash = &iter->ops->func_hash->notrace_hash; |
33dc9b12 | 4501 | |
058e297d | 4502 | mutex_lock(&ftrace_lock); |
3296fc4e | 4503 | old_hash = *orig_hash; |
7485058e SRRH |
4504 | old_hash_ops.filter_hash = iter->ops->func_hash->filter_hash; |
4505 | old_hash_ops.notrace_hash = iter->ops->func_hash->notrace_hash; | |
41fb61c2 SR |
4506 | ret = ftrace_hash_move(iter->ops, filter_hash, |
4507 | orig_hash, iter->hash); | |
3296fc4e | 4508 | if (!ret) { |
7485058e | 4509 | ftrace_ops_update_code(iter->ops, &old_hash_ops); |
3296fc4e SRRH |
4510 | free_ftrace_hash_rcu(old_hash); |
4511 | } | |
058e297d SR |
4512 | mutex_unlock(&ftrace_lock); |
4513 | } | |
3f2367ba | 4514 | |
33b7f99c | 4515 | mutex_unlock(&iter->ops->func_hash->regex_lock); |
33dc9b12 SR |
4516 | free_ftrace_hash(iter->hash); |
4517 | kfree(iter); | |
058e297d | 4518 | |
5072c59f SR |
4519 | return 0; |
4520 | } | |
4521 | ||
5e2336a0 | 4522 | static const struct file_operations ftrace_avail_fops = { |
5072c59f SR |
4523 | .open = ftrace_avail_open, |
4524 | .read = seq_read, | |
4525 | .llseek = seq_lseek, | |
3be04b47 | 4526 | .release = seq_release_private, |
5072c59f SR |
4527 | }; |
4528 | ||
647bcd03 SR |
4529 | static const struct file_operations ftrace_enabled_fops = { |
4530 | .open = ftrace_enabled_open, | |
4531 | .read = seq_read, | |
4532 | .llseek = seq_lseek, | |
4533 | .release = seq_release_private, | |
4534 | }; | |
4535 | ||
5e2336a0 | 4536 | static const struct file_operations ftrace_filter_fops = { |
5072c59f | 4537 | .open = ftrace_filter_open, |
850a80cf | 4538 | .read = seq_read, |
5072c59f | 4539 | .write = ftrace_filter_write, |
098c879e | 4540 | .llseek = tracing_lseek, |
1cf41dd7 | 4541 | .release = ftrace_regex_release, |
5072c59f SR |
4542 | }; |
4543 | ||
5e2336a0 | 4544 | static const struct file_operations ftrace_notrace_fops = { |
41c52c0d | 4545 | .open = ftrace_notrace_open, |
850a80cf | 4546 | .read = seq_read, |
41c52c0d | 4547 | .write = ftrace_notrace_write, |
098c879e | 4548 | .llseek = tracing_lseek, |
1cf41dd7 | 4549 | .release = ftrace_regex_release, |
41c52c0d SR |
4550 | }; |
4551 | ||
ea4e2bc4 SR |
4552 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
4553 | ||
4554 | static DEFINE_MUTEX(graph_lock); | |
4555 | ||
b9b0c831 NK |
4556 | struct ftrace_hash *ftrace_graph_hash = EMPTY_HASH; |
4557 | struct ftrace_hash *ftrace_graph_notrace_hash = EMPTY_HASH; | |
4558 | ||
4559 | enum graph_filter_type { | |
4560 | GRAPH_FILTER_NOTRACE = 0, | |
4561 | GRAPH_FILTER_FUNCTION, | |
4562 | }; | |
ea4e2bc4 | 4563 | |
555fc781 SRV |
4564 | #define FTRACE_GRAPH_EMPTY ((void *)1) |
4565 | ||
faf982a6 | 4566 | struct ftrace_graph_data { |
e704eff3 SRV |
4567 | struct ftrace_hash *hash; |
4568 | struct ftrace_func_entry *entry; | |
4569 | int idx; /* for hash table iteration */ | |
4570 | enum graph_filter_type type; | |
4571 | struct ftrace_hash *new_hash; | |
4572 | const struct seq_operations *seq_ops; | |
4573 | struct trace_parser parser; | |
faf982a6 NK |
4574 | }; |
4575 | ||
ea4e2bc4 | 4576 | static void * |
85951842 | 4577 | __g_next(struct seq_file *m, loff_t *pos) |
ea4e2bc4 | 4578 | { |
faf982a6 | 4579 | struct ftrace_graph_data *fgd = m->private; |
b9b0c831 NK |
4580 | struct ftrace_func_entry *entry = fgd->entry; |
4581 | struct hlist_head *head; | |
4582 | int i, idx = fgd->idx; | |
faf982a6 | 4583 | |
b9b0c831 | 4584 | if (*pos >= fgd->hash->count) |
ea4e2bc4 | 4585 | return NULL; |
b9b0c831 NK |
4586 | |
4587 | if (entry) { | |
4588 | hlist_for_each_entry_continue(entry, hlist) { | |
4589 | fgd->entry = entry; | |
4590 | return entry; | |
4591 | } | |
4592 | ||
4593 | idx++; | |
4594 | } | |
4595 | ||
4596 | for (i = idx; i < 1 << fgd->hash->size_bits; i++) { | |
4597 | head = &fgd->hash->buckets[i]; | |
4598 | hlist_for_each_entry(entry, head, hlist) { | |
4599 | fgd->entry = entry; | |
4600 | fgd->idx = i; | |
4601 | return entry; | |
4602 | } | |
4603 | } | |
4604 | return NULL; | |
85951842 | 4605 | } |
ea4e2bc4 | 4606 | |
85951842 LZ |
4607 | static void * |
4608 | g_next(struct seq_file *m, void *v, loff_t *pos) | |
4609 | { | |
4610 | (*pos)++; | |
4611 | return __g_next(m, pos); | |
ea4e2bc4 SR |
4612 | } |
4613 | ||
4614 | static void *g_start(struct seq_file *m, loff_t *pos) | |
4615 | { | |
faf982a6 NK |
4616 | struct ftrace_graph_data *fgd = m->private; |
4617 | ||
ea4e2bc4 SR |
4618 | mutex_lock(&graph_lock); |
4619 | ||
649b988b SRV |
4620 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
4621 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, | |
4622 | lockdep_is_held(&graph_lock)); | |
4623 | else | |
4624 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
4625 | lockdep_is_held(&graph_lock)); | |
4626 | ||
f9349a8f | 4627 | /* Nothing, tell g_show to print all functions are enabled */ |
b9b0c831 | 4628 | if (ftrace_hash_empty(fgd->hash) && !*pos) |
555fc781 | 4629 | return FTRACE_GRAPH_EMPTY; |
f9349a8f | 4630 | |
b9b0c831 NK |
4631 | fgd->idx = 0; |
4632 | fgd->entry = NULL; | |
85951842 | 4633 | return __g_next(m, pos); |
ea4e2bc4 SR |
4634 | } |
4635 | ||
4636 | static void g_stop(struct seq_file *m, void *p) | |
4637 | { | |
4638 | mutex_unlock(&graph_lock); | |
4639 | } | |
4640 | ||
4641 | static int g_show(struct seq_file *m, void *v) | |
4642 | { | |
b9b0c831 | 4643 | struct ftrace_func_entry *entry = v; |
ea4e2bc4 | 4644 | |
b9b0c831 | 4645 | if (!entry) |
ea4e2bc4 SR |
4646 | return 0; |
4647 | ||
555fc781 | 4648 | if (entry == FTRACE_GRAPH_EMPTY) { |
280d1429 NK |
4649 | struct ftrace_graph_data *fgd = m->private; |
4650 | ||
b9b0c831 | 4651 | if (fgd->type == GRAPH_FILTER_FUNCTION) |
fa6f0cc7 | 4652 | seq_puts(m, "#### all functions enabled ####\n"); |
280d1429 | 4653 | else |
fa6f0cc7 | 4654 | seq_puts(m, "#### no functions disabled ####\n"); |
f9349a8f FW |
4655 | return 0; |
4656 | } | |
4657 | ||
b9b0c831 | 4658 | seq_printf(m, "%ps\n", (void *)entry->ip); |
ea4e2bc4 SR |
4659 | |
4660 | return 0; | |
4661 | } | |
4662 | ||
88e9d34c | 4663 | static const struct seq_operations ftrace_graph_seq_ops = { |
ea4e2bc4 SR |
4664 | .start = g_start, |
4665 | .next = g_next, | |
4666 | .stop = g_stop, | |
4667 | .show = g_show, | |
4668 | }; | |
4669 | ||
4670 | static int | |
faf982a6 NK |
4671 | __ftrace_graph_open(struct inode *inode, struct file *file, |
4672 | struct ftrace_graph_data *fgd) | |
ea4e2bc4 SR |
4673 | { |
4674 | int ret = 0; | |
b9b0c831 | 4675 | struct ftrace_hash *new_hash = NULL; |
ea4e2bc4 | 4676 | |
b9b0c831 NK |
4677 | if (file->f_mode & FMODE_WRITE) { |
4678 | const int size_bits = FTRACE_HASH_DEFAULT_BITS; | |
4679 | ||
e704eff3 SRV |
4680 | if (trace_parser_get_init(&fgd->parser, FTRACE_BUFF_MAX)) |
4681 | return -ENOMEM; | |
4682 | ||
b9b0c831 NK |
4683 | if (file->f_flags & O_TRUNC) |
4684 | new_hash = alloc_ftrace_hash(size_bits); | |
4685 | else | |
4686 | new_hash = alloc_and_copy_ftrace_hash(size_bits, | |
4687 | fgd->hash); | |
4688 | if (!new_hash) { | |
4689 | ret = -ENOMEM; | |
4690 | goto out; | |
4691 | } | |
ea4e2bc4 SR |
4692 | } |
4693 | ||
faf982a6 | 4694 | if (file->f_mode & FMODE_READ) { |
b9b0c831 | 4695 | ret = seq_open(file, &ftrace_graph_seq_ops); |
faf982a6 NK |
4696 | if (!ret) { |
4697 | struct seq_file *m = file->private_data; | |
4698 | m->private = fgd; | |
b9b0c831 NK |
4699 | } else { |
4700 | /* Failed */ | |
4701 | free_ftrace_hash(new_hash); | |
4702 | new_hash = NULL; | |
faf982a6 NK |
4703 | } |
4704 | } else | |
4705 | file->private_data = fgd; | |
ea4e2bc4 | 4706 | |
b9b0c831 | 4707 | out: |
e704eff3 SRV |
4708 | if (ret < 0 && file->f_mode & FMODE_WRITE) |
4709 | trace_parser_put(&fgd->parser); | |
4710 | ||
b9b0c831 | 4711 | fgd->new_hash = new_hash; |
649b988b SRV |
4712 | |
4713 | /* | |
4714 | * All uses of fgd->hash must be taken with the graph_lock | |
4715 | * held. The graph_lock is going to be released, so force | |
4716 | * fgd->hash to be reinitialized when it is taken again. | |
4717 | */ | |
4718 | fgd->hash = NULL; | |
4719 | ||
ea4e2bc4 SR |
4720 | return ret; |
4721 | } | |
4722 | ||
faf982a6 NK |
4723 | static int |
4724 | ftrace_graph_open(struct inode *inode, struct file *file) | |
4725 | { | |
4726 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 4727 | int ret; |
faf982a6 NK |
4728 | |
4729 | if (unlikely(ftrace_disabled)) | |
4730 | return -ENODEV; | |
4731 | ||
4732 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
4733 | if (fgd == NULL) | |
4734 | return -ENOMEM; | |
4735 | ||
b9b0c831 NK |
4736 | mutex_lock(&graph_lock); |
4737 | ||
649b988b SRV |
4738 | fgd->hash = rcu_dereference_protected(ftrace_graph_hash, |
4739 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 4740 | fgd->type = GRAPH_FILTER_FUNCTION; |
faf982a6 NK |
4741 | fgd->seq_ops = &ftrace_graph_seq_ops; |
4742 | ||
b9b0c831 NK |
4743 | ret = __ftrace_graph_open(inode, file, fgd); |
4744 | if (ret < 0) | |
4745 | kfree(fgd); | |
4746 | ||
4747 | mutex_unlock(&graph_lock); | |
4748 | return ret; | |
faf982a6 NK |
4749 | } |
4750 | ||
29ad23b0 NK |
4751 | static int |
4752 | ftrace_graph_notrace_open(struct inode *inode, struct file *file) | |
4753 | { | |
4754 | struct ftrace_graph_data *fgd; | |
b9b0c831 | 4755 | int ret; |
29ad23b0 NK |
4756 | |
4757 | if (unlikely(ftrace_disabled)) | |
4758 | return -ENODEV; | |
4759 | ||
4760 | fgd = kmalloc(sizeof(*fgd), GFP_KERNEL); | |
4761 | if (fgd == NULL) | |
4762 | return -ENOMEM; | |
4763 | ||
b9b0c831 NK |
4764 | mutex_lock(&graph_lock); |
4765 | ||
649b988b SRV |
4766 | fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash, |
4767 | lockdep_is_held(&graph_lock)); | |
b9b0c831 | 4768 | fgd->type = GRAPH_FILTER_NOTRACE; |
29ad23b0 NK |
4769 | fgd->seq_ops = &ftrace_graph_seq_ops; |
4770 | ||
b9b0c831 NK |
4771 | ret = __ftrace_graph_open(inode, file, fgd); |
4772 | if (ret < 0) | |
4773 | kfree(fgd); | |
4774 | ||
4775 | mutex_unlock(&graph_lock); | |
4776 | return ret; | |
29ad23b0 NK |
4777 | } |
4778 | ||
87827111 LZ |
4779 | static int |
4780 | ftrace_graph_release(struct inode *inode, struct file *file) | |
4781 | { | |
b9b0c831 | 4782 | struct ftrace_graph_data *fgd; |
e704eff3 SRV |
4783 | struct ftrace_hash *old_hash, *new_hash; |
4784 | struct trace_parser *parser; | |
4785 | int ret = 0; | |
b9b0c831 | 4786 | |
faf982a6 NK |
4787 | if (file->f_mode & FMODE_READ) { |
4788 | struct seq_file *m = file->private_data; | |
4789 | ||
b9b0c831 | 4790 | fgd = m->private; |
87827111 | 4791 | seq_release(inode, file); |
faf982a6 | 4792 | } else { |
b9b0c831 | 4793 | fgd = file->private_data; |
faf982a6 NK |
4794 | } |
4795 | ||
e704eff3 SRV |
4796 | |
4797 | if (file->f_mode & FMODE_WRITE) { | |
4798 | ||
4799 | parser = &fgd->parser; | |
4800 | ||
4801 | if (trace_parser_loaded((parser))) { | |
4802 | parser->buffer[parser->idx] = 0; | |
4803 | ret = ftrace_graph_set_hash(fgd->new_hash, | |
4804 | parser->buffer); | |
4805 | } | |
4806 | ||
4807 | trace_parser_put(parser); | |
4808 | ||
4809 | new_hash = __ftrace_hash_move(fgd->new_hash); | |
4810 | if (!new_hash) { | |
4811 | ret = -ENOMEM; | |
4812 | goto out; | |
4813 | } | |
4814 | ||
4815 | mutex_lock(&graph_lock); | |
4816 | ||
4817 | if (fgd->type == GRAPH_FILTER_FUNCTION) { | |
4818 | old_hash = rcu_dereference_protected(ftrace_graph_hash, | |
4819 | lockdep_is_held(&graph_lock)); | |
4820 | rcu_assign_pointer(ftrace_graph_hash, new_hash); | |
4821 | } else { | |
4822 | old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, | |
4823 | lockdep_is_held(&graph_lock)); | |
4824 | rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash); | |
4825 | } | |
4826 | ||
4827 | mutex_unlock(&graph_lock); | |
4828 | ||
4829 | /* Wait till all users are no longer using the old hash */ | |
4830 | synchronize_sched(); | |
4831 | ||
4832 | free_ftrace_hash(old_hash); | |
4833 | } | |
4834 | ||
4835 | out: | |
b9b0c831 NK |
4836 | kfree(fgd->new_hash); |
4837 | kfree(fgd); | |
4838 | ||
e704eff3 | 4839 | return ret; |
87827111 LZ |
4840 | } |
4841 | ||
ea4e2bc4 | 4842 | static int |
b9b0c831 | 4843 | ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) |
ea4e2bc4 | 4844 | { |
3ba00929 | 4845 | struct ftrace_glob func_g; |
ea4e2bc4 SR |
4846 | struct dyn_ftrace *rec; |
4847 | struct ftrace_page *pg; | |
b9b0c831 | 4848 | struct ftrace_func_entry *entry; |
c7c6b1fe | 4849 | int fail = 1; |
3ba00929 | 4850 | int not; |
ea4e2bc4 | 4851 | |
f9349a8f | 4852 | /* decode regex */ |
3ba00929 DS |
4853 | func_g.type = filter_parse_regex(buffer, strlen(buffer), |
4854 | &func_g.search, ¬); | |
f9349a8f | 4855 | |
3ba00929 | 4856 | func_g.len = strlen(func_g.search); |
f9349a8f | 4857 | |
52baf119 | 4858 | mutex_lock(&ftrace_lock); |
45a4a237 SR |
4859 | |
4860 | if (unlikely(ftrace_disabled)) { | |
4861 | mutex_unlock(&ftrace_lock); | |
4862 | return -ENODEV; | |
4863 | } | |
4864 | ||
265c831c SR |
4865 | do_for_each_ftrace_rec(pg, rec) { |
4866 | ||
546fece4 SRRH |
4867 | if (rec->flags & FTRACE_FL_DISABLED) |
4868 | continue; | |
4869 | ||
0b507e1e | 4870 | if (ftrace_match_record(rec, &func_g, NULL, 0)) { |
b9b0c831 | 4871 | entry = ftrace_lookup_ip(hash, rec->ip); |
c7c6b1fe LZ |
4872 | |
4873 | if (!not) { | |
4874 | fail = 0; | |
b9b0c831 NK |
4875 | |
4876 | if (entry) | |
4877 | continue; | |
4878 | if (add_hash_entry(hash, rec->ip) < 0) | |
4879 | goto out; | |
c7c6b1fe | 4880 | } else { |
b9b0c831 NK |
4881 | if (entry) { |
4882 | free_hash_entry(hash, entry); | |
c7c6b1fe LZ |
4883 | fail = 0; |
4884 | } | |
4885 | } | |
ea4e2bc4 | 4886 | } |
265c831c | 4887 | } while_for_each_ftrace_rec(); |
c7c6b1fe | 4888 | out: |
52baf119 | 4889 | mutex_unlock(&ftrace_lock); |
ea4e2bc4 | 4890 | |
c7c6b1fe LZ |
4891 | if (fail) |
4892 | return -EINVAL; | |
4893 | ||
c7c6b1fe | 4894 | return 0; |
ea4e2bc4 SR |
4895 | } |
4896 | ||
4897 | static ssize_t | |
4898 | ftrace_graph_write(struct file *file, const char __user *ubuf, | |
4899 | size_t cnt, loff_t *ppos) | |
4900 | { | |
6a10108b | 4901 | ssize_t read, ret = 0; |
faf982a6 | 4902 | struct ftrace_graph_data *fgd = file->private_data; |
e704eff3 | 4903 | struct trace_parser *parser; |
ea4e2bc4 | 4904 | |
c7c6b1fe | 4905 | if (!cnt) |
ea4e2bc4 SR |
4906 | return 0; |
4907 | ||
ae98d27a SRV |
4908 | /* Read mode uses seq functions */ |
4909 | if (file->f_mode & FMODE_READ) { | |
4910 | struct seq_file *m = file->private_data; | |
4911 | fgd = m->private; | |
4912 | } | |
4913 | ||
e704eff3 | 4914 | parser = &fgd->parser; |
ea4e2bc4 | 4915 | |
e704eff3 | 4916 | read = trace_get_user(parser, ubuf, cnt, ppos); |
689fd8b6 | 4917 | |
e704eff3 SRV |
4918 | if (read >= 0 && trace_parser_loaded(parser) && |
4919 | !trace_parser_cont(parser)) { | |
6a10108b | 4920 | |
b9b0c831 | 4921 | ret = ftrace_graph_set_hash(fgd->new_hash, |
e704eff3 SRV |
4922 | parser->buffer); |
4923 | trace_parser_clear(parser); | |
ea4e2bc4 | 4924 | } |
ea4e2bc4 | 4925 | |
6a10108b NK |
4926 | if (!ret) |
4927 | ret = read; | |
1eb90f13 | 4928 | |
ea4e2bc4 SR |
4929 | return ret; |
4930 | } | |
4931 | ||
4932 | static const struct file_operations ftrace_graph_fops = { | |
87827111 LZ |
4933 | .open = ftrace_graph_open, |
4934 | .read = seq_read, | |
4935 | .write = ftrace_graph_write, | |
098c879e | 4936 | .llseek = tracing_lseek, |
87827111 | 4937 | .release = ftrace_graph_release, |
ea4e2bc4 | 4938 | }; |
29ad23b0 NK |
4939 | |
4940 | static const struct file_operations ftrace_graph_notrace_fops = { | |
4941 | .open = ftrace_graph_notrace_open, | |
4942 | .read = seq_read, | |
4943 | .write = ftrace_graph_write, | |
098c879e | 4944 | .llseek = tracing_lseek, |
29ad23b0 NK |
4945 | .release = ftrace_graph_release, |
4946 | }; | |
ea4e2bc4 SR |
4947 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
4948 | ||
591dffda SRRH |
4949 | void ftrace_create_filter_files(struct ftrace_ops *ops, |
4950 | struct dentry *parent) | |
4951 | { | |
4952 | ||
4953 | trace_create_file("set_ftrace_filter", 0644, parent, | |
4954 | ops, &ftrace_filter_fops); | |
4955 | ||
4956 | trace_create_file("set_ftrace_notrace", 0644, parent, | |
4957 | ops, &ftrace_notrace_fops); | |
4958 | } | |
4959 | ||
4960 | /* | |
4961 | * The name "destroy_filter_files" is really a misnomer. Although | |
4962 | * in the future, it may actualy delete the files, but this is | |
4963 | * really intended to make sure the ops passed in are disabled | |
4964 | * and that when this function returns, the caller is free to | |
4965 | * free the ops. | |
4966 | * | |
4967 | * The "destroy" name is only to match the "create" name that this | |
4968 | * should be paired with. | |
4969 | */ | |
4970 | void ftrace_destroy_filter_files(struct ftrace_ops *ops) | |
4971 | { | |
4972 | mutex_lock(&ftrace_lock); | |
4973 | if (ops->flags & FTRACE_OPS_FL_ENABLED) | |
4974 | ftrace_shutdown(ops, 0); | |
4975 | ops->flags |= FTRACE_OPS_FL_DELETED; | |
4976 | mutex_unlock(&ftrace_lock); | |
4977 | } | |
4978 | ||
8434dc93 | 4979 | static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) |
5072c59f | 4980 | { |
5072c59f | 4981 | |
5452af66 FW |
4982 | trace_create_file("available_filter_functions", 0444, |
4983 | d_tracer, NULL, &ftrace_avail_fops); | |
5072c59f | 4984 | |
647bcd03 SR |
4985 | trace_create_file("enabled_functions", 0444, |
4986 | d_tracer, NULL, &ftrace_enabled_fops); | |
4987 | ||
591dffda | 4988 | ftrace_create_filter_files(&global_ops, d_tracer); |
ad90c0e3 | 4989 | |
ea4e2bc4 | 4990 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
5452af66 | 4991 | trace_create_file("set_graph_function", 0444, d_tracer, |
ea4e2bc4 SR |
4992 | NULL, |
4993 | &ftrace_graph_fops); | |
29ad23b0 NK |
4994 | trace_create_file("set_graph_notrace", 0444, d_tracer, |
4995 | NULL, | |
4996 | &ftrace_graph_notrace_fops); | |
ea4e2bc4 SR |
4997 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
4998 | ||
5072c59f SR |
4999 | return 0; |
5000 | } | |
5001 | ||
9fd49328 | 5002 | static int ftrace_cmp_ips(const void *a, const void *b) |
68950619 | 5003 | { |
9fd49328 SR |
5004 | const unsigned long *ipa = a; |
5005 | const unsigned long *ipb = b; | |
68950619 | 5006 | |
9fd49328 SR |
5007 | if (*ipa > *ipb) |
5008 | return 1; | |
5009 | if (*ipa < *ipb) | |
5010 | return -1; | |
5011 | return 0; | |
5012 | } | |
5013 | ||
5cb084bb | 5014 | static int ftrace_process_locs(struct module *mod, |
31e88909 | 5015 | unsigned long *start, |
68bf21aa SR |
5016 | unsigned long *end) |
5017 | { | |
706c81f8 | 5018 | struct ftrace_page *start_pg; |
a7900875 | 5019 | struct ftrace_page *pg; |
706c81f8 | 5020 | struct dyn_ftrace *rec; |
a7900875 | 5021 | unsigned long count; |
68bf21aa SR |
5022 | unsigned long *p; |
5023 | unsigned long addr; | |
4376cac6 | 5024 | unsigned long flags = 0; /* Shut up gcc */ |
a7900875 SR |
5025 | int ret = -ENOMEM; |
5026 | ||
5027 | count = end - start; | |
5028 | ||
5029 | if (!count) | |
5030 | return 0; | |
5031 | ||
9fd49328 | 5032 | sort(start, count, sizeof(*start), |
6db02903 | 5033 | ftrace_cmp_ips, NULL); |
9fd49328 | 5034 | |
706c81f8 SR |
5035 | start_pg = ftrace_allocate_pages(count); |
5036 | if (!start_pg) | |
a7900875 | 5037 | return -ENOMEM; |
68bf21aa | 5038 | |
e6ea44e9 | 5039 | mutex_lock(&ftrace_lock); |
a7900875 | 5040 | |
32082309 SR |
5041 | /* |
5042 | * Core and each module needs their own pages, as | |
5043 | * modules will free them when they are removed. | |
5044 | * Force a new page to be allocated for modules. | |
5045 | */ | |
a7900875 SR |
5046 | if (!mod) { |
5047 | WARN_ON(ftrace_pages || ftrace_pages_start); | |
5048 | /* First initialization */ | |
706c81f8 | 5049 | ftrace_pages = ftrace_pages_start = start_pg; |
a7900875 | 5050 | } else { |
32082309 | 5051 | if (!ftrace_pages) |
a7900875 | 5052 | goto out; |
32082309 | 5053 | |
a7900875 SR |
5054 | if (WARN_ON(ftrace_pages->next)) { |
5055 | /* Hmm, we have free pages? */ | |
5056 | while (ftrace_pages->next) | |
5057 | ftrace_pages = ftrace_pages->next; | |
32082309 | 5058 | } |
a7900875 | 5059 | |
706c81f8 | 5060 | ftrace_pages->next = start_pg; |
32082309 SR |
5061 | } |
5062 | ||
68bf21aa | 5063 | p = start; |
706c81f8 | 5064 | pg = start_pg; |
68bf21aa SR |
5065 | while (p < end) { |
5066 | addr = ftrace_call_adjust(*p++); | |
20e5227e SR |
5067 | /* |
5068 | * Some architecture linkers will pad between | |
5069 | * the different mcount_loc sections of different | |
5070 | * object files to satisfy alignments. | |
5071 | * Skip any NULL pointers. | |
5072 | */ | |
5073 | if (!addr) | |
5074 | continue; | |
706c81f8 SR |
5075 | |
5076 | if (pg->index == pg->size) { | |
5077 | /* We should have allocated enough */ | |
5078 | if (WARN_ON(!pg->next)) | |
5079 | break; | |
5080 | pg = pg->next; | |
5081 | } | |
5082 | ||
5083 | rec = &pg->records[pg->index++]; | |
5084 | rec->ip = addr; | |
68bf21aa SR |
5085 | } |
5086 | ||
706c81f8 SR |
5087 | /* We should have used all pages */ |
5088 | WARN_ON(pg->next); | |
5089 | ||
5090 | /* Assign the last page to ftrace_pages */ | |
5091 | ftrace_pages = pg; | |
5092 | ||
a4f18ed1 | 5093 | /* |
4376cac6 SR |
5094 | * We only need to disable interrupts on start up |
5095 | * because we are modifying code that an interrupt | |
5096 | * may execute, and the modification is not atomic. | |
5097 | * But for modules, nothing runs the code we modify | |
5098 | * until we are finished with it, and there's no | |
5099 | * reason to cause large interrupt latencies while we do it. | |
a4f18ed1 | 5100 | */ |
4376cac6 SR |
5101 | if (!mod) |
5102 | local_irq_save(flags); | |
1dc43cf0 | 5103 | ftrace_update_code(mod, start_pg); |
4376cac6 SR |
5104 | if (!mod) |
5105 | local_irq_restore(flags); | |
a7900875 SR |
5106 | ret = 0; |
5107 | out: | |
e6ea44e9 | 5108 | mutex_unlock(&ftrace_lock); |
68bf21aa | 5109 | |
a7900875 | 5110 | return ret; |
68bf21aa SR |
5111 | } |
5112 | ||
93eb677d | 5113 | #ifdef CONFIG_MODULES |
32082309 SR |
5114 | |
5115 | #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) | |
5116 | ||
b7ffffbb SRRH |
5117 | static int referenced_filters(struct dyn_ftrace *rec) |
5118 | { | |
5119 | struct ftrace_ops *ops; | |
5120 | int cnt = 0; | |
5121 | ||
5122 | for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { | |
5123 | if (ops_references_rec(ops, rec)) | |
5124 | cnt++; | |
5125 | } | |
5126 | ||
5127 | return cnt; | |
5128 | } | |
5129 | ||
e7247a15 | 5130 | void ftrace_release_mod(struct module *mod) |
93eb677d SR |
5131 | { |
5132 | struct dyn_ftrace *rec; | |
32082309 | 5133 | struct ftrace_page **last_pg; |
93eb677d | 5134 | struct ftrace_page *pg; |
a7900875 | 5135 | int order; |
93eb677d | 5136 | |
45a4a237 SR |
5137 | mutex_lock(&ftrace_lock); |
5138 | ||
e7247a15 | 5139 | if (ftrace_disabled) |
45a4a237 | 5140 | goto out_unlock; |
93eb677d | 5141 | |
32082309 SR |
5142 | /* |
5143 | * Each module has its own ftrace_pages, remove | |
5144 | * them from the list. | |
5145 | */ | |
5146 | last_pg = &ftrace_pages_start; | |
5147 | for (pg = ftrace_pages_start; pg; pg = *last_pg) { | |
5148 | rec = &pg->records[0]; | |
e7247a15 | 5149 | if (within_module_core(rec->ip, mod)) { |
93eb677d | 5150 | /* |
32082309 SR |
5151 | * As core pages are first, the first |
5152 | * page should never be a module page. | |
93eb677d | 5153 | */ |
32082309 SR |
5154 | if (WARN_ON(pg == ftrace_pages_start)) |
5155 | goto out_unlock; | |
5156 | ||
5157 | /* Check if we are deleting the last page */ | |
5158 | if (pg == ftrace_pages) | |
5159 | ftrace_pages = next_to_ftrace_page(last_pg); | |
5160 | ||
5161 | *last_pg = pg->next; | |
a7900875 SR |
5162 | order = get_count_order(pg->size / ENTRIES_PER_PAGE); |
5163 | free_pages((unsigned long)pg->records, order); | |
5164 | kfree(pg); | |
32082309 SR |
5165 | } else |
5166 | last_pg = &pg->next; | |
5167 | } | |
45a4a237 | 5168 | out_unlock: |
93eb677d SR |
5169 | mutex_unlock(&ftrace_lock); |
5170 | } | |
5171 | ||
7dcd182b | 5172 | void ftrace_module_enable(struct module *mod) |
b7ffffbb SRRH |
5173 | { |
5174 | struct dyn_ftrace *rec; | |
5175 | struct ftrace_page *pg; | |
5176 | ||
5177 | mutex_lock(&ftrace_lock); | |
5178 | ||
5179 | if (ftrace_disabled) | |
5180 | goto out_unlock; | |
5181 | ||
5182 | /* | |
5183 | * If the tracing is enabled, go ahead and enable the record. | |
5184 | * | |
5185 | * The reason not to enable the record immediatelly is the | |
5186 | * inherent check of ftrace_make_nop/ftrace_make_call for | |
5187 | * correct previous instructions. Making first the NOP | |
5188 | * conversion puts the module to the correct state, thus | |
5189 | * passing the ftrace_make_call check. | |
5190 | * | |
5191 | * We also delay this to after the module code already set the | |
5192 | * text to read-only, as we now need to set it back to read-write | |
5193 | * so that we can modify the text. | |
5194 | */ | |
5195 | if (ftrace_start_up) | |
5196 | ftrace_arch_code_modify_prepare(); | |
5197 | ||
5198 | do_for_each_ftrace_rec(pg, rec) { | |
5199 | int cnt; | |
5200 | /* | |
5201 | * do_for_each_ftrace_rec() is a double loop. | |
5202 | * module text shares the pg. If a record is | |
5203 | * not part of this module, then skip this pg, | |
5204 | * which the "break" will do. | |
5205 | */ | |
5206 | if (!within_module_core(rec->ip, mod)) | |
5207 | break; | |
5208 | ||
5209 | cnt = 0; | |
5210 | ||
5211 | /* | |
5212 | * When adding a module, we need to check if tracers are | |
5213 | * currently enabled and if they are, and can trace this record, | |
5214 | * we need to enable the module functions as well as update the | |
5215 | * reference counts for those function records. | |
5216 | */ | |
5217 | if (ftrace_start_up) | |
5218 | cnt += referenced_filters(rec); | |
5219 | ||
5220 | /* This clears FTRACE_FL_DISABLED */ | |
5221 | rec->flags = cnt; | |
5222 | ||
5223 | if (ftrace_start_up && cnt) { | |
5224 | int failed = __ftrace_replace_code(rec, 1); | |
5225 | if (failed) { | |
5226 | ftrace_bug(failed, rec); | |
5227 | goto out_loop; | |
5228 | } | |
5229 | } | |
5230 | ||
5231 | } while_for_each_ftrace_rec(); | |
5232 | ||
5233 | out_loop: | |
5234 | if (ftrace_start_up) | |
5235 | ftrace_arch_code_modify_post_process(); | |
5236 | ||
5237 | out_unlock: | |
5238 | mutex_unlock(&ftrace_lock); | |
5239 | } | |
5240 | ||
b6b71f66 | 5241 | void ftrace_module_init(struct module *mod) |
90d595fe | 5242 | { |
97e9b4fc | 5243 | if (ftrace_disabled || !mod->num_ftrace_callsites) |
fed1939c | 5244 | return; |
90d595fe | 5245 | |
97e9b4fc SRRH |
5246 | ftrace_process_locs(mod, mod->ftrace_callsites, |
5247 | mod->ftrace_callsites + mod->num_ftrace_callsites); | |
8c189ea6 | 5248 | } |
93eb677d SR |
5249 | #endif /* CONFIG_MODULES */ |
5250 | ||
68bf21aa SR |
5251 | void __init ftrace_init(void) |
5252 | { | |
1dc43cf0 JS |
5253 | extern unsigned long __start_mcount_loc[]; |
5254 | extern unsigned long __stop_mcount_loc[]; | |
3a36cb11 | 5255 | unsigned long count, flags; |
68bf21aa SR |
5256 | int ret; |
5257 | ||
68bf21aa | 5258 | local_irq_save(flags); |
3a36cb11 | 5259 | ret = ftrace_dyn_arch_init(); |
68bf21aa | 5260 | local_irq_restore(flags); |
af64a7cb | 5261 | if (ret) |
68bf21aa SR |
5262 | goto failed; |
5263 | ||
5264 | count = __stop_mcount_loc - __start_mcount_loc; | |
c867ccd8 JS |
5265 | if (!count) { |
5266 | pr_info("ftrace: No functions to be traced?\n"); | |
68bf21aa | 5267 | goto failed; |
c867ccd8 JS |
5268 | } |
5269 | ||
5270 | pr_info("ftrace: allocating %ld entries in %ld pages\n", | |
5271 | count, count / ENTRIES_PER_PAGE + 1); | |
68bf21aa SR |
5272 | |
5273 | last_ftrace_enabled = ftrace_enabled = 1; | |
5274 | ||
5cb084bb | 5275 | ret = ftrace_process_locs(NULL, |
31e88909 | 5276 | __start_mcount_loc, |
68bf21aa SR |
5277 | __stop_mcount_loc); |
5278 | ||
2af15d6a SR |
5279 | set_ftrace_early_filters(); |
5280 | ||
68bf21aa SR |
5281 | return; |
5282 | failed: | |
5283 | ftrace_disabled = 1; | |
5284 | } | |
68bf21aa | 5285 | |
f3bea491 SRRH |
5286 | /* Do nothing if arch does not support this */ |
5287 | void __weak arch_ftrace_update_trampoline(struct ftrace_ops *ops) | |
5288 | { | |
5289 | } | |
5290 | ||
5291 | static void ftrace_update_trampoline(struct ftrace_ops *ops) | |
5292 | { | |
12cce594 SRRH |
5293 | |
5294 | /* | |
5295 | * Currently there's no safe way to free a trampoline when the kernel | |
5296 | * is configured with PREEMPT. That is because a task could be preempted | |
5297 | * when it jumped to the trampoline, it may be preempted for a long time | |
5298 | * depending on the system load, and currently there's no way to know | |
5299 | * when it will be off the trampoline. If the trampoline is freed | |
5300 | * too early, when the task runs again, it will be executing on freed | |
5301 | * memory and crash. | |
5302 | */ | |
5303 | #ifdef CONFIG_PREEMPT | |
f3bea491 SRRH |
5304 | /* Currently, only non dynamic ops can have a trampoline */ |
5305 | if (ops->flags & FTRACE_OPS_FL_DYNAMIC) | |
5306 | return; | |
12cce594 | 5307 | #endif |
f3bea491 SRRH |
5308 | |
5309 | arch_ftrace_update_trampoline(ops); | |
5310 | } | |
5311 | ||
3d083395 | 5312 | #else |
0b6e4d56 | 5313 | |
2b499381 | 5314 | static struct ftrace_ops global_ops = { |
bd69c30b | 5315 | .func = ftrace_stub, |
e3eea140 SRRH |
5316 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | |
5317 | FTRACE_OPS_FL_INITIALIZED | | |
5318 | FTRACE_OPS_FL_PID, | |
bd69c30b SR |
5319 | }; |
5320 | ||
0b6e4d56 FW |
5321 | static int __init ftrace_nodyn_init(void) |
5322 | { | |
5323 | ftrace_enabled = 1; | |
5324 | return 0; | |
5325 | } | |
6f415672 | 5326 | core_initcall(ftrace_nodyn_init); |
0b6e4d56 | 5327 | |
8434dc93 | 5328 | static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; } |
df4fc315 | 5329 | static inline void ftrace_startup_enable(int command) { } |
e1effa01 | 5330 | static inline void ftrace_startup_all(int command) { } |
5a45cfe1 | 5331 | /* Keep as macros so we do not need to define the commands */ |
8a56d776 SRRH |
5332 | # define ftrace_startup(ops, command) \ |
5333 | ({ \ | |
5334 | int ___ret = __register_ftrace_function(ops); \ | |
5335 | if (!___ret) \ | |
5336 | (ops)->flags |= FTRACE_OPS_FL_ENABLED; \ | |
5337 | ___ret; \ | |
3b6cfdb1 | 5338 | }) |
1fcc1553 SRRH |
5339 | # define ftrace_shutdown(ops, command) \ |
5340 | ({ \ | |
5341 | int ___ret = __unregister_ftrace_function(ops); \ | |
5342 | if (!___ret) \ | |
5343 | (ops)->flags &= ~FTRACE_OPS_FL_ENABLED; \ | |
5344 | ___ret; \ | |
5345 | }) | |
8a56d776 | 5346 | |
c7aafc54 IM |
5347 | # define ftrace_startup_sysctl() do { } while (0) |
5348 | # define ftrace_shutdown_sysctl() do { } while (0) | |
b848914c SR |
5349 | |
5350 | static inline int | |
195a8afc | 5351 | ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs) |
b848914c SR |
5352 | { |
5353 | return 1; | |
5354 | } | |
5355 | ||
f3bea491 SRRH |
5356 | static void ftrace_update_trampoline(struct ftrace_ops *ops) |
5357 | { | |
5358 | } | |
5359 | ||
3d083395 SR |
5360 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
5361 | ||
4104d326 SRRH |
5362 | __init void ftrace_init_global_array_ops(struct trace_array *tr) |
5363 | { | |
5364 | tr->ops = &global_ops; | |
5365 | tr->ops->private = tr; | |
5366 | } | |
5367 | ||
5368 | void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) | |
5369 | { | |
5370 | /* If we filter on pids, update to use the pid function */ | |
5371 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
5372 | if (WARN_ON(tr->ops->func != ftrace_stub)) | |
5373 | printk("ftrace ops had %pS for function\n", | |
5374 | tr->ops->func); | |
4104d326 SRRH |
5375 | } |
5376 | tr->ops->func = func; | |
5377 | tr->ops->private = tr; | |
5378 | } | |
5379 | ||
5380 | void ftrace_reset_array_ops(struct trace_array *tr) | |
5381 | { | |
5382 | tr->ops->func = ftrace_stub; | |
5383 | } | |
5384 | ||
2f5f6ad9 SR |
5385 | static inline void |
5386 | __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 5387 | struct ftrace_ops *ignored, struct pt_regs *regs) |
b848914c | 5388 | { |
cdbe61bf | 5389 | struct ftrace_ops *op; |
edc15caf | 5390 | int bit; |
b848914c | 5391 | |
edc15caf SR |
5392 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
5393 | if (bit < 0) | |
5394 | return; | |
b1cff0ad | 5395 | |
cdbe61bf SR |
5396 | /* |
5397 | * Some of the ops may be dynamically allocated, | |
5398 | * they must be freed after a synchronize_sched(). | |
5399 | */ | |
5400 | preempt_disable_notrace(); | |
ba27f2bc | 5401 | |
0a016409 | 5402 | do_for_each_ftrace_op(op, ftrace_ops_list) { |
ba27f2bc SRRH |
5403 | /* |
5404 | * Check the following for each ops before calling their func: | |
5405 | * if RCU flag is set, then rcu_is_watching() must be true | |
5406 | * if PER_CPU is set, then ftrace_function_local_disable() | |
5407 | * must be false | |
5408 | * Otherwise test if the ip matches the ops filter | |
5409 | * | |
5410 | * If any of the above fails then the op->func() is not executed. | |
5411 | */ | |
5412 | if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) && | |
5413 | (!(op->flags & FTRACE_OPS_FL_PER_CPU) || | |
5414 | !ftrace_function_local_disabled(op)) && | |
5415 | ftrace_ops_test(op, ip, regs)) { | |
5416 | ||
1d48d596 SRRH |
5417 | if (FTRACE_WARN_ON(!op->func)) { |
5418 | pr_warn("op=%p %pS\n", op, op); | |
4104d326 SRRH |
5419 | goto out; |
5420 | } | |
a1e2e31d | 5421 | op->func(ip, parent_ip, op, regs); |
4104d326 | 5422 | } |
0a016409 | 5423 | } while_for_each_ftrace_op(op); |
4104d326 | 5424 | out: |
cdbe61bf | 5425 | preempt_enable_notrace(); |
edc15caf | 5426 | trace_clear_recursion(bit); |
b848914c SR |
5427 | } |
5428 | ||
2f5f6ad9 SR |
5429 | /* |
5430 | * Some archs only support passing ip and parent_ip. Even though | |
5431 | * the list function ignores the op parameter, we do not want any | |
5432 | * C side effects, where a function is called without the caller | |
5433 | * sending a third parameter. | |
a1e2e31d SR |
5434 | * Archs are to support both the regs and ftrace_ops at the same time. |
5435 | * If they support ftrace_ops, it is assumed they support regs. | |
5436 | * If call backs want to use regs, they must either check for regs | |
06aeaaea MH |
5437 | * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS. |
5438 | * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved. | |
a1e2e31d | 5439 | * An architecture can pass partial regs with ftrace_ops and still |
b8ec330a | 5440 | * set the ARCH_SUPPORTS_FTRACE_OPS. |
2f5f6ad9 SR |
5441 | */ |
5442 | #if ARCH_SUPPORTS_FTRACE_OPS | |
5443 | static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip, | |
a1e2e31d | 5444 | struct ftrace_ops *op, struct pt_regs *regs) |
2f5f6ad9 | 5445 | { |
a1e2e31d | 5446 | __ftrace_ops_list_func(ip, parent_ip, NULL, regs); |
2f5f6ad9 SR |
5447 | } |
5448 | #else | |
5449 | static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip) | |
5450 | { | |
a1e2e31d | 5451 | __ftrace_ops_list_func(ip, parent_ip, NULL, NULL); |
2f5f6ad9 SR |
5452 | } |
5453 | #endif | |
5454 | ||
f1ff6348 SRRH |
5455 | /* |
5456 | * If there's only one function registered but it does not support | |
c68c0fa2 SRRH |
5457 | * recursion, needs RCU protection and/or requires per cpu handling, then |
5458 | * this function will be called by the mcount trampoline. | |
f1ff6348 | 5459 | */ |
c68c0fa2 | 5460 | static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip, |
f1ff6348 SRRH |
5461 | struct ftrace_ops *op, struct pt_regs *regs) |
5462 | { | |
5463 | int bit; | |
5464 | ||
c68c0fa2 SRRH |
5465 | if ((op->flags & FTRACE_OPS_FL_RCU) && !rcu_is_watching()) |
5466 | return; | |
5467 | ||
f1ff6348 SRRH |
5468 | bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX); |
5469 | if (bit < 0) | |
5470 | return; | |
5471 | ||
c68c0fa2 | 5472 | preempt_disable_notrace(); |
f1ff6348 | 5473 | |
c68c0fa2 SRRH |
5474 | if (!(op->flags & FTRACE_OPS_FL_PER_CPU) || |
5475 | !ftrace_function_local_disabled(op)) { | |
5476 | op->func(ip, parent_ip, op, regs); | |
5477 | } | |
5478 | ||
5479 | preempt_enable_notrace(); | |
f1ff6348 SRRH |
5480 | trace_clear_recursion(bit); |
5481 | } | |
5482 | ||
87354059 SRRH |
5483 | /** |
5484 | * ftrace_ops_get_func - get the function a trampoline should call | |
5485 | * @ops: the ops to get the function for | |
5486 | * | |
5487 | * Normally the mcount trampoline will call the ops->func, but there | |
5488 | * are times that it should not. For example, if the ops does not | |
5489 | * have its own recursion protection, then it should call the | |
5490 | * ftrace_ops_recurs_func() instead. | |
5491 | * | |
5492 | * Returns the function that the trampoline should call for @ops. | |
5493 | */ | |
5494 | ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops) | |
5495 | { | |
87354059 | 5496 | /* |
c68c0fa2 SRRH |
5497 | * If the function does not handle recursion, needs to be RCU safe, |
5498 | * or does per cpu logic, then we need to call the assist handler. | |
87354059 | 5499 | */ |
c68c0fa2 SRRH |
5500 | if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE) || |
5501 | ops->flags & (FTRACE_OPS_FL_RCU | FTRACE_OPS_FL_PER_CPU)) | |
5502 | return ftrace_ops_assist_func; | |
87354059 SRRH |
5503 | |
5504 | return ops->func; | |
5505 | } | |
5506 | ||
345ddcc8 SRRH |
5507 | static void |
5508 | ftrace_filter_pid_sched_switch_probe(void *data, bool preempt, | |
5509 | struct task_struct *prev, struct task_struct *next) | |
978f3a45 | 5510 | { |
345ddcc8 SRRH |
5511 | struct trace_array *tr = data; |
5512 | struct trace_pid_list *pid_list; | |
978f3a45 | 5513 | |
345ddcc8 | 5514 | pid_list = rcu_dereference_sched(tr->function_pids); |
e32d8956 | 5515 | |
345ddcc8 SRRH |
5516 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, |
5517 | trace_ignore_this_task(pid_list, next)); | |
978f3a45 SR |
5518 | } |
5519 | ||
345ddcc8 | 5520 | static void clear_ftrace_pids(struct trace_array *tr) |
e32d8956 | 5521 | { |
345ddcc8 SRRH |
5522 | struct trace_pid_list *pid_list; |
5523 | int cpu; | |
e32d8956 | 5524 | |
345ddcc8 SRRH |
5525 | pid_list = rcu_dereference_protected(tr->function_pids, |
5526 | lockdep_is_held(&ftrace_lock)); | |
5527 | if (!pid_list) | |
5528 | return; | |
229c4ef8 | 5529 | |
345ddcc8 | 5530 | unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); |
e32d8956 | 5531 | |
345ddcc8 SRRH |
5532 | for_each_possible_cpu(cpu) |
5533 | per_cpu_ptr(tr->trace_buffer.data, cpu)->ftrace_ignore_pid = false; | |
978f3a45 | 5534 | |
345ddcc8 | 5535 | rcu_assign_pointer(tr->function_pids, NULL); |
978f3a45 | 5536 | |
345ddcc8 SRRH |
5537 | /* Wait till all users are no longer using pid filtering */ |
5538 | synchronize_sched(); | |
e32d8956 | 5539 | |
345ddcc8 | 5540 | trace_free_pid_list(pid_list); |
e32d8956 SR |
5541 | } |
5542 | ||
345ddcc8 | 5543 | static void ftrace_pid_reset(struct trace_array *tr) |
df4fc315 | 5544 | { |
756d17ee | 5545 | mutex_lock(&ftrace_lock); |
345ddcc8 | 5546 | clear_ftrace_pids(tr); |
978f3a45 | 5547 | |
756d17ee | 5548 | ftrace_update_pid_func(); |
e1effa01 | 5549 | ftrace_startup_all(0); |
756d17ee | 5550 | |
5551 | mutex_unlock(&ftrace_lock); | |
756d17ee | 5552 | } |
5553 | ||
345ddcc8 SRRH |
5554 | /* Greater than any max PID */ |
5555 | #define FTRACE_NO_PIDS (void *)(PID_MAX_LIMIT + 1) | |
df4fc315 | 5556 | |
756d17ee | 5557 | static void *fpid_start(struct seq_file *m, loff_t *pos) |
345ddcc8 | 5558 | __acquires(RCU) |
756d17ee | 5559 | { |
345ddcc8 SRRH |
5560 | struct trace_pid_list *pid_list; |
5561 | struct trace_array *tr = m->private; | |
5562 | ||
756d17ee | 5563 | mutex_lock(&ftrace_lock); |
345ddcc8 SRRH |
5564 | rcu_read_lock_sched(); |
5565 | ||
5566 | pid_list = rcu_dereference_sched(tr->function_pids); | |
756d17ee | 5567 | |
345ddcc8 SRRH |
5568 | if (!pid_list) |
5569 | return !(*pos) ? FTRACE_NO_PIDS : NULL; | |
756d17ee | 5570 | |
345ddcc8 | 5571 | return trace_pid_start(pid_list, pos); |
756d17ee | 5572 | } |
5573 | ||
5574 | static void *fpid_next(struct seq_file *m, void *v, loff_t *pos) | |
5575 | { | |
345ddcc8 SRRH |
5576 | struct trace_array *tr = m->private; |
5577 | struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids); | |
5578 | ||
5579 | if (v == FTRACE_NO_PIDS) | |
756d17ee | 5580 | return NULL; |
5581 | ||
345ddcc8 | 5582 | return trace_pid_next(pid_list, v, pos); |
756d17ee | 5583 | } |
5584 | ||
5585 | static void fpid_stop(struct seq_file *m, void *p) | |
345ddcc8 | 5586 | __releases(RCU) |
756d17ee | 5587 | { |
345ddcc8 | 5588 | rcu_read_unlock_sched(); |
756d17ee | 5589 | mutex_unlock(&ftrace_lock); |
5590 | } | |
5591 | ||
5592 | static int fpid_show(struct seq_file *m, void *v) | |
5593 | { | |
345ddcc8 | 5594 | if (v == FTRACE_NO_PIDS) { |
fa6f0cc7 | 5595 | seq_puts(m, "no pid\n"); |
756d17ee | 5596 | return 0; |
5597 | } | |
5598 | ||
345ddcc8 | 5599 | return trace_pid_show(m, v); |
756d17ee | 5600 | } |
5601 | ||
5602 | static const struct seq_operations ftrace_pid_sops = { | |
5603 | .start = fpid_start, | |
5604 | .next = fpid_next, | |
5605 | .stop = fpid_stop, | |
5606 | .show = fpid_show, | |
5607 | }; | |
5608 | ||
5609 | static int | |
5610 | ftrace_pid_open(struct inode *inode, struct file *file) | |
5611 | { | |
345ddcc8 SRRH |
5612 | struct trace_array *tr = inode->i_private; |
5613 | struct seq_file *m; | |
756d17ee | 5614 | int ret = 0; |
5615 | ||
345ddcc8 SRRH |
5616 | if (trace_array_get(tr) < 0) |
5617 | return -ENODEV; | |
5618 | ||
756d17ee | 5619 | if ((file->f_mode & FMODE_WRITE) && |
5620 | (file->f_flags & O_TRUNC)) | |
345ddcc8 | 5621 | ftrace_pid_reset(tr); |
756d17ee | 5622 | |
345ddcc8 SRRH |
5623 | ret = seq_open(file, &ftrace_pid_sops); |
5624 | if (ret < 0) { | |
5625 | trace_array_put(tr); | |
5626 | } else { | |
5627 | m = file->private_data; | |
5628 | /* copy tr over to seq ops */ | |
5629 | m->private = tr; | |
5630 | } | |
756d17ee | 5631 | |
5632 | return ret; | |
5633 | } | |
5634 | ||
345ddcc8 SRRH |
5635 | static void ignore_task_cpu(void *data) |
5636 | { | |
5637 | struct trace_array *tr = data; | |
5638 | struct trace_pid_list *pid_list; | |
5639 | ||
5640 | /* | |
5641 | * This function is called by on_each_cpu() while the | |
5642 | * event_mutex is held. | |
5643 | */ | |
5644 | pid_list = rcu_dereference_protected(tr->function_pids, | |
5645 | mutex_is_locked(&ftrace_lock)); | |
5646 | ||
5647 | this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid, | |
5648 | trace_ignore_this_task(pid_list, current)); | |
5649 | } | |
5650 | ||
df4fc315 SR |
5651 | static ssize_t |
5652 | ftrace_pid_write(struct file *filp, const char __user *ubuf, | |
5653 | size_t cnt, loff_t *ppos) | |
5654 | { | |
345ddcc8 SRRH |
5655 | struct seq_file *m = filp->private_data; |
5656 | struct trace_array *tr = m->private; | |
5657 | struct trace_pid_list *filtered_pids = NULL; | |
5658 | struct trace_pid_list *pid_list; | |
5659 | ssize_t ret; | |
df4fc315 | 5660 | |
345ddcc8 SRRH |
5661 | if (!cnt) |
5662 | return 0; | |
5663 | ||
5664 | mutex_lock(&ftrace_lock); | |
5665 | ||
5666 | filtered_pids = rcu_dereference_protected(tr->function_pids, | |
5667 | lockdep_is_held(&ftrace_lock)); | |
5668 | ||
5669 | ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); | |
5670 | if (ret < 0) | |
5671 | goto out; | |
df4fc315 | 5672 | |
345ddcc8 | 5673 | rcu_assign_pointer(tr->function_pids, pid_list); |
df4fc315 | 5674 | |
345ddcc8 SRRH |
5675 | if (filtered_pids) { |
5676 | synchronize_sched(); | |
5677 | trace_free_pid_list(filtered_pids); | |
5678 | } else if (pid_list) { | |
5679 | /* Register a probe to set whether to ignore the tracing of a task */ | |
5680 | register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr); | |
5681 | } | |
df4fc315 | 5682 | |
756d17ee | 5683 | /* |
345ddcc8 SRRH |
5684 | * Ignoring of pids is done at task switch. But we have to |
5685 | * check for those tasks that are currently running. | |
5686 | * Always do this in case a pid was appended or removed. | |
756d17ee | 5687 | */ |
345ddcc8 | 5688 | on_each_cpu(ignore_task_cpu, tr, 1); |
756d17ee | 5689 | |
345ddcc8 SRRH |
5690 | ftrace_update_pid_func(); |
5691 | ftrace_startup_all(0); | |
5692 | out: | |
5693 | mutex_unlock(&ftrace_lock); | |
df4fc315 | 5694 | |
345ddcc8 SRRH |
5695 | if (ret > 0) |
5696 | *ppos += ret; | |
df4fc315 | 5697 | |
345ddcc8 | 5698 | return ret; |
756d17ee | 5699 | } |
df4fc315 | 5700 | |
756d17ee | 5701 | static int |
5702 | ftrace_pid_release(struct inode *inode, struct file *file) | |
5703 | { | |
345ddcc8 | 5704 | struct trace_array *tr = inode->i_private; |
df4fc315 | 5705 | |
345ddcc8 SRRH |
5706 | trace_array_put(tr); |
5707 | ||
5708 | return seq_release(inode, file); | |
df4fc315 SR |
5709 | } |
5710 | ||
5e2336a0 | 5711 | static const struct file_operations ftrace_pid_fops = { |
756d17ee | 5712 | .open = ftrace_pid_open, |
5713 | .write = ftrace_pid_write, | |
5714 | .read = seq_read, | |
098c879e | 5715 | .llseek = tracing_lseek, |
756d17ee | 5716 | .release = ftrace_pid_release, |
df4fc315 SR |
5717 | }; |
5718 | ||
345ddcc8 | 5719 | void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
df4fc315 | 5720 | { |
5452af66 | 5721 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
345ddcc8 | 5722 | tr, &ftrace_pid_fops); |
df4fc315 | 5723 | } |
df4fc315 | 5724 | |
501c2375 SRRH |
5725 | void __init ftrace_init_tracefs_toplevel(struct trace_array *tr, |
5726 | struct dentry *d_tracer) | |
5727 | { | |
5728 | /* Only the top level directory has the dyn_tracefs and profile */ | |
5729 | WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); | |
5730 | ||
5731 | ftrace_init_dyn_tracefs(d_tracer); | |
5732 | ftrace_profile_tracefs(d_tracer); | |
5733 | } | |
5734 | ||
a2bb6a3d | 5735 | /** |
81adbdc0 | 5736 | * ftrace_kill - kill ftrace |
a2bb6a3d SR |
5737 | * |
5738 | * This function should be used by panic code. It stops ftrace | |
5739 | * but in a not so nice way. If you need to simply kill ftrace | |
5740 | * from a non-atomic section, use ftrace_kill. | |
5741 | */ | |
81adbdc0 | 5742 | void ftrace_kill(void) |
a2bb6a3d SR |
5743 | { |
5744 | ftrace_disabled = 1; | |
5745 | ftrace_enabled = 0; | |
a2bb6a3d SR |
5746 | clear_ftrace_function(); |
5747 | } | |
5748 | ||
e0a413f6 SR |
5749 | /** |
5750 | * Test if ftrace is dead or not. | |
5751 | */ | |
5752 | int ftrace_is_dead(void) | |
5753 | { | |
5754 | return ftrace_disabled; | |
5755 | } | |
5756 | ||
16444a8a | 5757 | /** |
3d083395 SR |
5758 | * register_ftrace_function - register a function for profiling |
5759 | * @ops - ops structure that holds the function for profiling. | |
16444a8a | 5760 | * |
3d083395 SR |
5761 | * Register a function to be called by all functions in the |
5762 | * kernel. | |
5763 | * | |
5764 | * Note: @ops->func and all the functions it calls must be labeled | |
5765 | * with "notrace", otherwise it will go into a | |
5766 | * recursive loop. | |
16444a8a | 5767 | */ |
3d083395 | 5768 | int register_ftrace_function(struct ftrace_ops *ops) |
16444a8a | 5769 | { |
45a4a237 | 5770 | int ret = -1; |
4eebcc81 | 5771 | |
f04f24fb MH |
5772 | ftrace_ops_init(ops); |
5773 | ||
e6ea44e9 | 5774 | mutex_lock(&ftrace_lock); |
e7d3737e | 5775 | |
8a56d776 | 5776 | ret = ftrace_startup(ops, 0); |
b848914c | 5777 | |
e6ea44e9 | 5778 | mutex_unlock(&ftrace_lock); |
8d240dd8 | 5779 | |
b0fc494f | 5780 | return ret; |
3d083395 | 5781 | } |
cdbe61bf | 5782 | EXPORT_SYMBOL_GPL(register_ftrace_function); |
3d083395 SR |
5783 | |
5784 | /** | |
32632920 | 5785 | * unregister_ftrace_function - unregister a function for profiling. |
3d083395 SR |
5786 | * @ops - ops structure that holds the function to unregister |
5787 | * | |
5788 | * Unregister a function that was added to be called by ftrace profiling. | |
5789 | */ | |
5790 | int unregister_ftrace_function(struct ftrace_ops *ops) | |
5791 | { | |
5792 | int ret; | |
5793 | ||
e6ea44e9 | 5794 | mutex_lock(&ftrace_lock); |
8a56d776 | 5795 | ret = ftrace_shutdown(ops, 0); |
e6ea44e9 | 5796 | mutex_unlock(&ftrace_lock); |
b0fc494f SR |
5797 | |
5798 | return ret; | |
5799 | } | |
cdbe61bf | 5800 | EXPORT_SYMBOL_GPL(unregister_ftrace_function); |
b0fc494f | 5801 | |
e309b41d | 5802 | int |
b0fc494f | 5803 | ftrace_enable_sysctl(struct ctl_table *table, int write, |
8d65af78 | 5804 | void __user *buffer, size_t *lenp, |
b0fc494f SR |
5805 | loff_t *ppos) |
5806 | { | |
45a4a237 | 5807 | int ret = -ENODEV; |
4eebcc81 | 5808 | |
e6ea44e9 | 5809 | mutex_lock(&ftrace_lock); |
b0fc494f | 5810 | |
45a4a237 SR |
5811 | if (unlikely(ftrace_disabled)) |
5812 | goto out; | |
5813 | ||
5814 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
b0fc494f | 5815 | |
a32c7765 | 5816 | if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled)) |
b0fc494f SR |
5817 | goto out; |
5818 | ||
a32c7765 | 5819 | last_ftrace_enabled = !!ftrace_enabled; |
b0fc494f SR |
5820 | |
5821 | if (ftrace_enabled) { | |
5822 | ||
b0fc494f | 5823 | /* we are starting ftrace again */ |
5000c418 JK |
5824 | if (ftrace_ops_list != &ftrace_list_end) |
5825 | update_ftrace_function(); | |
b0fc494f | 5826 | |
524a3868 SRRH |
5827 | ftrace_startup_sysctl(); |
5828 | ||
b0fc494f SR |
5829 | } else { |
5830 | /* stopping ftrace calls (just send to ftrace_stub) */ | |
5831 | ftrace_trace_function = ftrace_stub; | |
5832 | ||
5833 | ftrace_shutdown_sysctl(); | |
5834 | } | |
5835 | ||
5836 | out: | |
e6ea44e9 | 5837 | mutex_unlock(&ftrace_lock); |
3d083395 | 5838 | return ret; |
16444a8a | 5839 | } |
f17845e5 | 5840 | |
fb52607a | 5841 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e7d3737e | 5842 | |
5f151b24 SRRH |
5843 | static struct ftrace_ops graph_ops = { |
5844 | .func = ftrace_stub, | |
5845 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | | |
5846 | FTRACE_OPS_FL_INITIALIZED | | |
e3eea140 | 5847 | FTRACE_OPS_FL_PID | |
5f151b24 SRRH |
5848 | FTRACE_OPS_FL_STUB, |
5849 | #ifdef FTRACE_GRAPH_TRAMP_ADDR | |
5850 | .trampoline = FTRACE_GRAPH_TRAMP_ADDR, | |
aec0be2d | 5851 | /* trampoline_size is only needed for dynamically allocated tramps */ |
5f151b24 SRRH |
5852 | #endif |
5853 | ASSIGN_OPS_HASH(graph_ops, &global_ops.local_hash) | |
5854 | }; | |
5855 | ||
55577204 SRRH |
5856 | void ftrace_graph_sleep_time_control(bool enable) |
5857 | { | |
5858 | fgraph_sleep_time = enable; | |
5859 | } | |
5860 | ||
5861 | void ftrace_graph_graph_time_control(bool enable) | |
5862 | { | |
5863 | fgraph_graph_time = enable; | |
5864 | } | |
5865 | ||
e49dc19c SR |
5866 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
5867 | { | |
5868 | return 0; | |
5869 | } | |
5870 | ||
287b6e68 FW |
5871 | /* The callbacks that hook a function */ |
5872 | trace_func_graph_ret_t ftrace_graph_return = | |
5873 | (trace_func_graph_ret_t)ftrace_stub; | |
e49dc19c | 5874 | trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; |
23a8e844 | 5875 | static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub; |
f201ae23 FW |
5876 | |
5877 | /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ | |
5878 | static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |
5879 | { | |
5880 | int i; | |
5881 | int ret = 0; | |
f201ae23 FW |
5882 | int start = 0, end = FTRACE_RETSTACK_ALLOC_SIZE; |
5883 | struct task_struct *g, *t; | |
5884 | ||
5885 | for (i = 0; i < FTRACE_RETSTACK_ALLOC_SIZE; i++) { | |
5886 | ret_stack_list[i] = kmalloc(FTRACE_RETFUNC_DEPTH | |
5887 | * sizeof(struct ftrace_ret_stack), | |
5888 | GFP_KERNEL); | |
5889 | if (!ret_stack_list[i]) { | |
5890 | start = 0; | |
5891 | end = i; | |
5892 | ret = -ENOMEM; | |
5893 | goto free; | |
5894 | } | |
5895 | } | |
5896 | ||
6112a300 | 5897 | read_lock(&tasklist_lock); |
f201ae23 FW |
5898 | do_each_thread(g, t) { |
5899 | if (start == end) { | |
5900 | ret = -EAGAIN; | |
5901 | goto unlock; | |
5902 | } | |
5903 | ||
5904 | if (t->ret_stack == NULL) { | |
380c4b14 | 5905 | atomic_set(&t->tracing_graph_pause, 0); |
f201ae23 | 5906 | atomic_set(&t->trace_overrun, 0); |
26c01624 SR |
5907 | t->curr_ret_stack = -1; |
5908 | /* Make sure the tasks see the -1 first: */ | |
5909 | smp_wmb(); | |
5910 | t->ret_stack = ret_stack_list[start++]; | |
f201ae23 FW |
5911 | } |
5912 | } while_each_thread(g, t); | |
5913 | ||
5914 | unlock: | |
6112a300 | 5915 | read_unlock(&tasklist_lock); |
f201ae23 FW |
5916 | free: |
5917 | for (i = start; i < end; i++) | |
5918 | kfree(ret_stack_list[i]); | |
5919 | return ret; | |
5920 | } | |
5921 | ||
8aef2d28 | 5922 | static void |
c73464b1 | 5923 | ftrace_graph_probe_sched_switch(void *ignore, bool preempt, |
38516ab5 | 5924 | struct task_struct *prev, struct task_struct *next) |
8aef2d28 SR |
5925 | { |
5926 | unsigned long long timestamp; | |
5927 | int index; | |
5928 | ||
be6f164a SR |
5929 | /* |
5930 | * Does the user want to count the time a function was asleep. | |
5931 | * If so, do not update the time stamps. | |
5932 | */ | |
55577204 | 5933 | if (fgraph_sleep_time) |
be6f164a SR |
5934 | return; |
5935 | ||
8aef2d28 SR |
5936 | timestamp = trace_clock_local(); |
5937 | ||
5938 | prev->ftrace_timestamp = timestamp; | |
5939 | ||
5940 | /* only process tasks that we timestamped */ | |
5941 | if (!next->ftrace_timestamp) | |
5942 | return; | |
5943 | ||
5944 | /* | |
5945 | * Update all the counters in next to make up for the | |
5946 | * time next was sleeping. | |
5947 | */ | |
5948 | timestamp -= next->ftrace_timestamp; | |
5949 | ||
5950 | for (index = next->curr_ret_stack; index >= 0; index--) | |
5951 | next->ret_stack[index].calltime += timestamp; | |
5952 | } | |
5953 | ||
f201ae23 | 5954 | /* Allocate a return stack for each task */ |
fb52607a | 5955 | static int start_graph_tracing(void) |
f201ae23 FW |
5956 | { |
5957 | struct ftrace_ret_stack **ret_stack_list; | |
5b058bcd | 5958 | int ret, cpu; |
f201ae23 FW |
5959 | |
5960 | ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE * | |
5961 | sizeof(struct ftrace_ret_stack *), | |
5962 | GFP_KERNEL); | |
5963 | ||
5964 | if (!ret_stack_list) | |
5965 | return -ENOMEM; | |
5966 | ||
5b058bcd | 5967 | /* The cpu_boot init_task->ret_stack will never be freed */ |
179c498a SR |
5968 | for_each_online_cpu(cpu) { |
5969 | if (!idle_task(cpu)->ret_stack) | |
868baf07 | 5970 | ftrace_graph_init_idle_task(idle_task(cpu), cpu); |
179c498a | 5971 | } |
5b058bcd | 5972 | |
f201ae23 FW |
5973 | do { |
5974 | ret = alloc_retstack_tasklist(ret_stack_list); | |
5975 | } while (ret == -EAGAIN); | |
5976 | ||
8aef2d28 | 5977 | if (!ret) { |
38516ab5 | 5978 | ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
8aef2d28 SR |
5979 | if (ret) |
5980 | pr_info("ftrace_graph: Couldn't activate tracepoint" | |
5981 | " probe to kernel_sched_switch\n"); | |
5982 | } | |
5983 | ||
f201ae23 FW |
5984 | kfree(ret_stack_list); |
5985 | return ret; | |
5986 | } | |
5987 | ||
4a2b8dda FW |
5988 | /* |
5989 | * Hibernation protection. | |
5990 | * The state of the current task is too much unstable during | |
5991 | * suspend/restore to disk. We want to protect against that. | |
5992 | */ | |
5993 | static int | |
5994 | ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state, | |
5995 | void *unused) | |
5996 | { | |
5997 | switch (state) { | |
5998 | case PM_HIBERNATION_PREPARE: | |
5999 | pause_graph_tracing(); | |
6000 | break; | |
6001 | ||
6002 | case PM_POST_HIBERNATION: | |
6003 | unpause_graph_tracing(); | |
6004 | break; | |
6005 | } | |
6006 | return NOTIFY_DONE; | |
6007 | } | |
6008 | ||
23a8e844 SRRH |
6009 | static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace) |
6010 | { | |
6011 | if (!ftrace_ops_test(&global_ops, trace->func, NULL)) | |
6012 | return 0; | |
6013 | return __ftrace_graph_entry(trace); | |
6014 | } | |
6015 | ||
6016 | /* | |
6017 | * The function graph tracer should only trace the functions defined | |
6018 | * by set_ftrace_filter and set_ftrace_notrace. If another function | |
6019 | * tracer ops is registered, the graph tracer requires testing the | |
6020 | * function against the global ops, and not just trace any function | |
6021 | * that any ftrace_ops registered. | |
6022 | */ | |
6023 | static void update_function_graph_func(void) | |
6024 | { | |
5f151b24 SRRH |
6025 | struct ftrace_ops *op; |
6026 | bool do_test = false; | |
6027 | ||
6028 | /* | |
6029 | * The graph and global ops share the same set of functions | |
6030 | * to test. If any other ops is on the list, then | |
6031 | * the graph tracing needs to test if its the function | |
6032 | * it should call. | |
6033 | */ | |
6034 | do_for_each_ftrace_op(op, ftrace_ops_list) { | |
6035 | if (op != &global_ops && op != &graph_ops && | |
6036 | op != &ftrace_list_end) { | |
6037 | do_test = true; | |
6038 | /* in double loop, break out with goto */ | |
6039 | goto out; | |
6040 | } | |
6041 | } while_for_each_ftrace_op(op); | |
6042 | out: | |
6043 | if (do_test) | |
23a8e844 | 6044 | ftrace_graph_entry = ftrace_graph_entry_test; |
5f151b24 SRRH |
6045 | else |
6046 | ftrace_graph_entry = __ftrace_graph_entry; | |
23a8e844 SRRH |
6047 | } |
6048 | ||
8275f69f MK |
6049 | static struct notifier_block ftrace_suspend_notifier = { |
6050 | .notifier_call = ftrace_suspend_notifier_call, | |
6051 | }; | |
6052 | ||
287b6e68 FW |
6053 | int register_ftrace_graph(trace_func_graph_ret_t retfunc, |
6054 | trace_func_graph_ent_t entryfunc) | |
15e6cb36 | 6055 | { |
e7d3737e FW |
6056 | int ret = 0; |
6057 | ||
e6ea44e9 | 6058 | mutex_lock(&ftrace_lock); |
e7d3737e | 6059 | |
05ce5818 | 6060 | /* we currently allow only one tracer registered at a time */ |
597af815 | 6061 | if (ftrace_graph_active) { |
05ce5818 SR |
6062 | ret = -EBUSY; |
6063 | goto out; | |
6064 | } | |
6065 | ||
4a2b8dda FW |
6066 | register_pm_notifier(&ftrace_suspend_notifier); |
6067 | ||
597af815 | 6068 | ftrace_graph_active++; |
fb52607a | 6069 | ret = start_graph_tracing(); |
f201ae23 | 6070 | if (ret) { |
597af815 | 6071 | ftrace_graph_active--; |
f201ae23 FW |
6072 | goto out; |
6073 | } | |
e53a6319 | 6074 | |
287b6e68 | 6075 | ftrace_graph_return = retfunc; |
23a8e844 SRRH |
6076 | |
6077 | /* | |
6078 | * Update the indirect function to the entryfunc, and the | |
6079 | * function that gets called to the entry_test first. Then | |
6080 | * call the update fgraph entry function to determine if | |
6081 | * the entryfunc should be called directly or not. | |
6082 | */ | |
6083 | __ftrace_graph_entry = entryfunc; | |
6084 | ftrace_graph_entry = ftrace_graph_entry_test; | |
6085 | update_function_graph_func(); | |
e53a6319 | 6086 | |
5f151b24 | 6087 | ret = ftrace_startup(&graph_ops, FTRACE_START_FUNC_RET); |
e7d3737e | 6088 | out: |
e6ea44e9 | 6089 | mutex_unlock(&ftrace_lock); |
e7d3737e | 6090 | return ret; |
15e6cb36 FW |
6091 | } |
6092 | ||
fb52607a | 6093 | void unregister_ftrace_graph(void) |
15e6cb36 | 6094 | { |
e6ea44e9 | 6095 | mutex_lock(&ftrace_lock); |
e7d3737e | 6096 | |
597af815 | 6097 | if (unlikely(!ftrace_graph_active)) |
2aad1b76 SR |
6098 | goto out; |
6099 | ||
597af815 | 6100 | ftrace_graph_active--; |
287b6e68 | 6101 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
e49dc19c | 6102 | ftrace_graph_entry = ftrace_graph_entry_stub; |
23a8e844 | 6103 | __ftrace_graph_entry = ftrace_graph_entry_stub; |
5f151b24 | 6104 | ftrace_shutdown(&graph_ops, FTRACE_STOP_FUNC_RET); |
4a2b8dda | 6105 | unregister_pm_notifier(&ftrace_suspend_notifier); |
38516ab5 | 6106 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); |
e7d3737e | 6107 | |
f3bea491 SRRH |
6108 | #ifdef CONFIG_DYNAMIC_FTRACE |
6109 | /* | |
6110 | * Function graph does not allocate the trampoline, but | |
6111 | * other global_ops do. We need to reset the ALLOC_TRAMP flag | |
6112 | * if one was used. | |
6113 | */ | |
6114 | global_ops.trampoline = save_global_trampoline; | |
6115 | if (save_global_flags & FTRACE_OPS_FL_ALLOC_TRAMP) | |
6116 | global_ops.flags |= FTRACE_OPS_FL_ALLOC_TRAMP; | |
6117 | #endif | |
6118 | ||
2aad1b76 | 6119 | out: |
e6ea44e9 | 6120 | mutex_unlock(&ftrace_lock); |
15e6cb36 | 6121 | } |
f201ae23 | 6122 | |
868baf07 SR |
6123 | static DEFINE_PER_CPU(struct ftrace_ret_stack *, idle_ret_stack); |
6124 | ||
6125 | static void | |
6126 | graph_init_task(struct task_struct *t, struct ftrace_ret_stack *ret_stack) | |
6127 | { | |
6128 | atomic_set(&t->tracing_graph_pause, 0); | |
6129 | atomic_set(&t->trace_overrun, 0); | |
6130 | t->ftrace_timestamp = 0; | |
25985edc | 6131 | /* make curr_ret_stack visible before we add the ret_stack */ |
868baf07 SR |
6132 | smp_wmb(); |
6133 | t->ret_stack = ret_stack; | |
6134 | } | |
6135 | ||
6136 | /* | |
6137 | * Allocate a return stack for the idle task. May be the first | |
6138 | * time through, or it may be done by CPU hotplug online. | |
6139 | */ | |
6140 | void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) | |
6141 | { | |
6142 | t->curr_ret_stack = -1; | |
6143 | /* | |
6144 | * The idle task has no parent, it either has its own | |
6145 | * stack or no stack at all. | |
6146 | */ | |
6147 | if (t->ret_stack) | |
6148 | WARN_ON(t->ret_stack != per_cpu(idle_ret_stack, cpu)); | |
6149 | ||
6150 | if (ftrace_graph_active) { | |
6151 | struct ftrace_ret_stack *ret_stack; | |
6152 | ||
6153 | ret_stack = per_cpu(idle_ret_stack, cpu); | |
6154 | if (!ret_stack) { | |
6155 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
6156 | * sizeof(struct ftrace_ret_stack), | |
6157 | GFP_KERNEL); | |
6158 | if (!ret_stack) | |
6159 | return; | |
6160 | per_cpu(idle_ret_stack, cpu) = ret_stack; | |
6161 | } | |
6162 | graph_init_task(t, ret_stack); | |
6163 | } | |
6164 | } | |
6165 | ||
f201ae23 | 6166 | /* Allocate a return stack for newly created task */ |
fb52607a | 6167 | void ftrace_graph_init_task(struct task_struct *t) |
f201ae23 | 6168 | { |
84047e36 SR |
6169 | /* Make sure we do not use the parent ret_stack */ |
6170 | t->ret_stack = NULL; | |
ea14eb71 | 6171 | t->curr_ret_stack = -1; |
84047e36 | 6172 | |
597af815 | 6173 | if (ftrace_graph_active) { |
82310a32 SR |
6174 | struct ftrace_ret_stack *ret_stack; |
6175 | ||
6176 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | |
f201ae23 FW |
6177 | * sizeof(struct ftrace_ret_stack), |
6178 | GFP_KERNEL); | |
82310a32 | 6179 | if (!ret_stack) |
f201ae23 | 6180 | return; |
868baf07 | 6181 | graph_init_task(t, ret_stack); |
84047e36 | 6182 | } |
f201ae23 FW |
6183 | } |
6184 | ||
fb52607a | 6185 | void ftrace_graph_exit_task(struct task_struct *t) |
f201ae23 | 6186 | { |
eae849ca FW |
6187 | struct ftrace_ret_stack *ret_stack = t->ret_stack; |
6188 | ||
f201ae23 | 6189 | t->ret_stack = NULL; |
eae849ca FW |
6190 | /* NULL must become visible to IRQs before we free it: */ |
6191 | barrier(); | |
6192 | ||
6193 | kfree(ret_stack); | |
f201ae23 | 6194 | } |
15e6cb36 | 6195 | #endif |